/*
  Copyright (C) 2009-2018  Brazil
  Copyright (C) 2018-2024  Sutou Kouhei <kou@clear-code.com>
  Copyright (C) 2021       Horimoto Yasuhiro <horimoto@clear-code.com>

  This library is free software; you can redistribute it and/or
  modify it under the terms of the GNU Lesser General Public
  License as published by the Free Software Foundation; either
  version 2.1 of the License, or (at your option) any later version.

  This library is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public
  License along with this library; if not, write to the Free Software
  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
*/

#include "grn.h"
#include "grn_tokenizer.h"

#include "grn_accessor.h"
#include "grn_aggregators.h"
#include "grn_config.h"
#include "grn_db.h"
#include "grn_obj.h"
#include "grn_hash.h"
#include "grn_pat.h"
#include "grn_dat.h"
#include "grn_ii.h"
#include "grn_index_column.h"
#include "grn_ctx_impl.h"
#include "grn_table.h"
#include "grn_table_selector.h"
#include "grn_token_cursor.h"
#include "grn_tokenizers.h"
#include "grn_token_filters.h"
#include "grn_proc.h"
#include "grn_plugin.h"
#include "grn_geo.h"
#include "grn_generated_column.h"
#include "grn_scorers.h"
#include "grn_snip.h"
#include "grn_string.h"
#include "grn_normalizer.h"
#include "grn_report.h"
#include "grn_util.h"
#include "grn_cache.h"
#include "grn_window_functions.h"
#include "grn_expr.h"
#include "grn_cast.h"
#include "grn_token_column.h"
#include "grn_type.h"
#include "grn_posting.h"
#include "grn_vector.h"
#include "grn_index_cursor.h"
#include "grn_wal.h"

#include <math.h>
#include <string.h>
#include <sys/stat.h>

#ifdef WIN32
#  include <share.h>
#endif

static const uint32_t GRN_TABLE_PAT_KEY_CACHE_SIZE = 1 << 15;

#define WITH_NORMALIZE(table, key, key_size, block)                            \
  do {                                                                         \
    if (GRN_BULK_VSIZE(&((table)->normalizers)) > 0 && key && key_size > 0) {  \
      grn_obj *nstr;                                                           \
      if ((nstr =                                                              \
             grn_string_open(ctx, key, key_size, (grn_obj *)(table), 0))) {    \
        const char *key;                                                       \
        unsigned int key_size;                                                 \
        grn_string_get_normalized(ctx, nstr, &key, &key_size, NULL);           \
        do {                                                                   \
          block                                                                \
        } while (false);                                                       \
        grn_obj_close(ctx, nstr);                                              \
      } else {                                                                 \
        char name[GRN_TABLE_MAX_KEY_SIZE];                                     \
        int name_size;                                                         \
        name_size =                                                            \
          grn_obj_name(ctx, (grn_obj *)(table), name, GRN_TABLE_MAX_KEY_SIZE); \
        ERR(GRN_INVALID_ARGUMENT,                                              \
            "[key][normalize] failed to normalize: <%.*s>: <%.*s>(%d)",        \
            name_size,                                                         \
            name,                                                              \
            (int)key_size,                                                     \
            (const char *)key,                                                 \
            (int)key_size);                                                    \
      }                                                                        \
    } else {                                                                   \
      block                                                                    \
    }                                                                          \
  } while (false)

static inline grn_id
grn_table_add_v_inline(grn_ctx *ctx,
                       grn_obj *table,
                       const void *key,
                       int key_size,
                       void **value,
                       int *added);
static inline grn_id
grn_table_cursor_next_inline(grn_ctx *ctx, grn_table_cursor *tc);
static inline int
grn_table_cursor_get_value_inline(grn_ctx *ctx,
                                  grn_table_cursor *tc,
                                  void **value);

static bool grn_enable_reference_count = false;

static uint32_t grn_n_opening_dbs = 0;
static char grn_db_key[GRN_ENV_BUFFER_SIZE];

void
grn_db_init_from_env(void)
{
  grn_getenv("GRN_DB_KEY", grn_db_key, GRN_ENV_BUFFER_SIZE);
  {
    char grn_enable_reference_count_env[GRN_ENV_BUFFER_SIZE];
    grn_getenv("GRN_ENABLE_REFERENCE_COUNT",
               grn_enable_reference_count_env,
               GRN_ENV_BUFFER_SIZE);
    if (grn_enable_reference_count_env[0]) {
      if (strncmp(grn_enable_reference_count_env, "yes", strlen("yes")) == 0) {
        grn_enable_reference_count = true;
      } else {
        grn_enable_reference_count = false;
      }
    }
  }
}

bool
grn_is_reference_count_enable(void)
{
  return grn_enable_reference_count;
}

grn_rc
grn_set_reference_count_enable(bool enable)
{
  if (grn_n_opening_dbs != 0) {
    return GRN_OPERATION_NOT_PERMITTED;
  }
  grn_enable_reference_count = enable;
  return GRN_SUCCESS;
}

const char *
grn_hook_entry_to_string(grn_hook_entry entry)
{
  switch (entry) {
  case GRN_HOOK_SET:
    return "set";
  case GRN_HOOK_GET:
    return "get";
  case GRN_HOOK_INSERT:
    return "insert";
  case GRN_HOOK_DELETE:
    return "delete";
  case GRN_HOOK_SELECT:
    return "select";
  default:
    return "unknown";
  }
}

static inline void
gen_pathname(const char *path, char *buffer, int fno)
{
  size_t len = strlen(path);
  grn_memcpy(buffer, path, len);
  if (fno >= 0) {
    buffer[len] = '.';
    grn_itoh(fno, buffer + len + 1, 7);
    buffer[len + 8] = '\0';
  } else {
    buffer[len] = '\0';
  }
}

void
grn_db_generate_pathname(grn_ctx *ctx, grn_obj *db, grn_id id, char *buffer)
{
  gen_pathname(grn_obj_get_io(ctx, db)->path, buffer, id);
}

typedef struct {
  grn_obj *ptr;
  uint32_t lock;
  uint32_t done;
} db_value;

static const char *GRN_DB_CONFIG_PATH_FORMAT = "%s.conf";

static bool
grn_db_config_create(grn_ctx *ctx,
                     grn_db *s,
                     const char *path,
                     const char *context_tag)
{
  char *config_path;
  char config_path_buffer[PATH_MAX];
  uint32_t flags = GRN_OBJ_KEY_VAR_SIZE;

  if (path) {
    grn_snprintf(config_path_buffer,
                 PATH_MAX,
                 PATH_MAX,
                 GRN_DB_CONFIG_PATH_FORMAT,
                 path);
    config_path = config_path_buffer;
  } else {
    config_path = NULL;
  }
  s->config = grn_hash_create(ctx,
                              config_path,
                              GRN_CONFIG_MAX_KEY_SIZE,
                              GRN_CONFIG_VALUE_SPACE_SIZE,
                              flags);
  if (!s->config) {
    ERR(GRN_NO_MEMORY_AVAILABLE,
        "%s failed to create data store for configuration: <%s>",
        context_tag,
        config_path ? config_path : "(temporary)");
    return false;
  }

  return true;
}

static bool
grn_db_config_open(grn_ctx *ctx, grn_db *s, const char *path)
{
  char config_path[PATH_MAX];

  grn_snprintf(config_path,
               PATH_MAX,
               PATH_MAX,
               GRN_DB_CONFIG_PATH_FORMAT,
               path);
  if (grn_path_exist(config_path)) {
    s->config = grn_hash_open(ctx, config_path);
    if (!s->config) {
      ERR(GRN_NO_MEMORY_AVAILABLE,
          "[db][open] failed to open data store for configuration: <%s>",
          config_path);
      return false;
    }
    return true;
  } else {
    return grn_db_config_create(ctx, s, path, "[db][open]");
  }
}

static grn_rc
grn_db_config_remove(grn_ctx *ctx, const char *path)
{
  char config_path[PATH_MAX];

  grn_snprintf(config_path,
               PATH_MAX,
               PATH_MAX,
               GRN_DB_CONFIG_PATH_FORMAT,
               path);
  return grn_hash_remove(ctx, config_path);
}

grn_obj *
grn_db_create(grn_ctx *ctx, const char *path, grn_db_create_optarg *optarg)
{
  grn_db *s = NULL;

  GRN_API_ENTER;

  if (path && strlen(path) > PATH_MAX - 14) {
    ERR(GRN_INVALID_ARGUMENT, "too long path");
    goto exit;
  }

  s = GRN_MALLOC(sizeof(grn_db));
  if (!s) {
    ERR(GRN_NO_MEMORY_AVAILABLE, "grn_db alloc failed");
    goto exit;
  }

  CRITICAL_SECTION_INIT(s->lock);
  grn_tiny_array_init(ctx,
                      &s->values,
                      sizeof(db_value),
                      GRN_TINY_ARRAY_CLEAR | GRN_TINY_ARRAY_THREADSAFE |
                        GRN_TINY_ARRAY_USE_MALLOC);
  s->keys = NULL;
  s->specs = NULL;
  s->config = NULL;
  s->cache = NULL;
  s->options = NULL;
  s->is_closing = false;
  s->deferred_unrefs =
    grn_array_create(ctx, NULL, sizeof(grn_deferred_unref), GRN_TABLE_NO_KEY);
  s->is_deferred_unrefing = false;

  {
    bool use_default_db_key = true;
    bool use_pat_as_db_keys = false;
    if (grn_db_key[0]) {
      if (!strcmp(grn_db_key, "pat")) {
        use_default_db_key = false;
        use_pat_as_db_keys = true;
      } else if (!strcmp(grn_db_key, "dat")) {
        use_default_db_key = false;
      }
    }

    if (use_default_db_key && !strcmp(GRN_DEFAULT_DB_KEY, "pat")) {
      use_pat_as_db_keys = true;
    }
    if (use_pat_as_db_keys) {
      s->keys = (grn_obj *)grn_pat_create(ctx,
                                          path,
                                          GRN_TABLE_MAX_KEY_SIZE,
                                          0,
                                          GRN_OBJ_KEY_VAR_SIZE);
    } else {
      s->keys = (grn_obj *)grn_dat_create(ctx,
                                          path,
                                          GRN_TABLE_MAX_KEY_SIZE,
                                          0,
                                          GRN_OBJ_KEY_VAR_SIZE);
    }
  }

  if (!s->keys) {
    goto exit;
  }

  GRN_DB_OBJ_SET_TYPE(s, GRN_DB);
  s->obj.db = (grn_obj *)s;
  s->obj.header.domain = GRN_ID_NIL;
  DB_OBJ(&s->obj)->range = GRN_ID_NIL;
  /* prepare builtin classes and load builtin plugins. */
  if (path) {
    {
      char specs_path[PATH_MAX];
      gen_pathname(path, specs_path, 0);
      s->specs = grn_ja_create(ctx, specs_path, 65536, 0);
      if (!s->specs) {
        ERR(GRN_NO_MEMORY_AVAILABLE,
            "failed to create specs: <%s>",
            specs_path);
        goto exit;
      }
    }
  }

  if (!grn_db_config_create(ctx, s, path, "[db][create]")) {
    goto exit;
  }
  s->options = grn_options_create(ctx, path, "[db][create]");
  if (!s->options) {
    goto exit;
  }
  grn_ctx_use(ctx, (grn_obj *)s);
  grn_db_init_builtin_types(ctx);
  if (ctx->rc != GRN_SUCCESS) {
    goto exit;
  }
  if (path) {
    grn_obj_flush(ctx, (grn_obj *)s);
    if (ctx->rc != GRN_SUCCESS) {
      goto exit;
    }
  }
  {
    uint32_t current_n_opening_dbs;
    GRN_ATOMIC_ADD_EX(&grn_n_opening_dbs, 1, current_n_opening_dbs);
  }
  GRN_API_RETURN((grn_obj *)s);

exit:
  if (s) {
    if (s->keys) {
      if (s->keys->header.type == GRN_TABLE_PAT_KEY) {
        grn_pat_close(ctx, (grn_pat *)s->keys);
        grn_pat_remove(ctx, path);
      } else {
        grn_dat_close(ctx, (grn_dat *)s->keys);
        grn_dat_remove(ctx, path);
      }
    }
    if (s->specs) {
      const char *specs_path;
      char specs_path_copy[PATH_MAX];
      specs_path = grn_obj_path(ctx, (grn_obj *)(s->specs));
      grn_strcpy(specs_path_copy, sizeof(specs_path_copy), specs_path);
      grn_ja_close(ctx, s->specs);
      grn_ja_remove(ctx, specs_path_copy);
    }
    if (s->config) {
      grn_hash_close(ctx, s->config);
      grn_db_config_remove(ctx, path);
    }
    if (s->options) {
      grn_options_close(ctx, s->options);
      grn_options_remove(ctx, path);
    }
    grn_tiny_array_fin(&s->values);
    CRITICAL_SECTION_FIN(s->lock);
    GRN_FREE(s);
  }

  GRN_API_RETURN(NULL);
}

#define GRN_TYPE_FLOAT32_NAME     "Float32"
#define GRN_TYPE_FLOAT32_NAME_LEN (sizeof(GRN_TYPE_FLOAT32_NAME) - 1)
#define GRN_TYPE_FLOAT32_FLAGS    GRN_OBJ_KEY_FLOAT
#define GRN_TYPE_FLOAT32_SIZE     sizeof(float)

static bool
grn_db_open_ensure_float32(grn_ctx *ctx, grn_db *db)
{
  if (grn_table_get(ctx,
                    db->keys,
                    GRN_TYPE_FLOAT32_NAME,
                    GRN_TYPE_FLOAT32_NAME_LEN) == GRN_DB_FLOAT32) {
    return false;
  }

  if (db->keys->header.type != GRN_TABLE_DAT_KEY) {
    return false;
  }

  if (grn_table_update_by_id(ctx,
                             db->keys,
                             GRN_DB_FLOAT32,
                             GRN_TYPE_FLOAT32_NAME,
                             GRN_TYPE_FLOAT32_NAME_LEN) != GRN_SUCCESS) {
    return false;
  }

  grn_obj *float32 = grn_type_create_internal(ctx,
                                              GRN_DB_FLOAT32,
                                              GRN_TYPE_FLOAT32_FLAGS,
                                              GRN_TYPE_FLOAT32_SIZE);
  return float32 != NULL;
}

#define GRN_TYPE_BFLOAT16_NAME     "BFloat16"
#define GRN_TYPE_BFLOAT16_NAME_LEN (sizeof(GRN_TYPE_BFLOAT16_NAME) - 1)
#define GRN_TYPE_BFLOAT16_FLAGS    GRN_OBJ_KEY_FLOAT
#ifdef GRN_HAVE_BFLOAT16
#  define GRN_TYPE_BFLOAT16_SIZE sizeof(grn_bfloat16)
#else
#  define GRN_TYPE_BFLOAT16_SIZE sizeof(uint16_t)
#endif

static bool
grn_db_open_ensure_bfloat16(grn_ctx *ctx, grn_db *db)
{
  if (grn_table_get(ctx,
                    db->keys,
                    GRN_TYPE_BFLOAT16_NAME,
                    GRN_TYPE_BFLOAT16_NAME_LEN) == GRN_DB_BFLOAT16) {
    return false;
  }

  if (db->keys->header.type != GRN_TABLE_DAT_KEY) {
    return false;
  }

  if (grn_table_update_by_id(ctx,
                             db->keys,
                             GRN_DB_BFLOAT16,
                             GRN_TYPE_BFLOAT16_NAME,
                             GRN_TYPE_BFLOAT16_NAME_LEN) != GRN_SUCCESS) {
    return false;
  }

  grn_obj *bfloat16 = grn_type_create_internal(ctx,
                                               GRN_DB_BFLOAT16,
                                               GRN_TYPE_BFLOAT16_FLAGS,
                                               GRN_TYPE_BFLOAT16_SIZE);
  return bfloat16 != NULL;
}

grn_obj *
grn_db_open(grn_ctx *ctx, const char *path)
{
  grn_db *s = NULL;

  GRN_API_ENTER;

  if (!path) {
    ERR(GRN_INVALID_ARGUMENT, "[db][open] path is missing");
    goto exit;
  }

  if (strlen(path) > PATH_MAX - 14) {
    ERR(GRN_INVALID_ARGUMENT, "inappropriate path");
    goto exit;
  }

  s = GRN_MALLOC(sizeof(grn_db));
  if (!s) {
    ERR(GRN_NO_MEMORY_AVAILABLE, "grn_db alloc failed");
    goto exit;
  }

  CRITICAL_SECTION_INIT(s->lock);
  grn_tiny_array_init(ctx,
                      &s->values,
                      sizeof(db_value),
                      GRN_TINY_ARRAY_CLEAR | GRN_TINY_ARRAY_THREADSAFE |
                        GRN_TINY_ARRAY_USE_MALLOC);
  s->keys = NULL;
  s->specs = NULL;
  s->config = NULL;
  s->cache = NULL;
  s->options = NULL;
  s->is_closing = false;
  s->deferred_unrefs =
    grn_array_create(ctx, NULL, sizeof(grn_deferred_unref), GRN_TABLE_NO_KEY);
  s->is_deferred_unrefing = false;

  {
    uint32_t type = grn_io_detect_type(ctx, path);
    switch (type) {
    case GRN_TABLE_PAT_KEY:
      s->keys = (grn_obj *)grn_pat_open(ctx, path);
      break;
    case GRN_TABLE_DAT_KEY:
      s->keys = (grn_obj *)grn_dat_open(ctx, path);
      break;
    default:
      s->keys = NULL;
      if (ctx->rc == GRN_SUCCESS) {
        ERR(GRN_INVALID_ARGUMENT,
            "[db][open] invalid keys table's type: %#x",
            type);
        goto exit;
      }
      break;
    }
  }

  if (!s->keys) {
    goto exit;
  }

  {
    char specs_path[PATH_MAX];
    gen_pathname(path, specs_path, 0);
    s->specs = grn_ja_open(ctx, specs_path);
    if (!s->specs) {
      ERR(GRN_NO_MEMORY_AVAILABLE,
          "[db][open] failed to open specs: <%s>",
          specs_path);
      goto exit;
    }
  }
  if (!grn_db_config_open(ctx, s, path)) {
    goto exit;
  }
  s->options = grn_options_open(ctx, path, "[db][open]");
  if (!s->options) {
    goto exit;
  }

  GRN_DB_OBJ_SET_TYPE(s, GRN_DB);
  s->obj.db = (grn_obj *)s;
  s->obj.header.domain = GRN_ID_NIL;
  DB_OBJ(&s->obj)->range = GRN_ID_NIL;
  grn_ctx_use(ctx, (grn_obj *)s);
  {
    bool need_flush = false;
    unsigned int n_records;

    n_records = grn_table_size(ctx, (grn_obj *)s);
    if (grn_db_open_ensure_float32(ctx, s)) {
      need_flush = true;
    }
    if (grn_db_open_ensure_bfloat16(ctx, s)) {
      need_flush = true;
    }
#ifdef GRN_WITH_MECAB
    if (grn_db_init_mecab_tokenizer(ctx)) {
      ERRCLR(ctx);
    }
#endif
    grn_db_init_builtin_tokenizers(ctx);
    grn_db_init_builtin_normalizers(ctx);
    grn_db_init_builtin_scorers(ctx);
    grn_db_init_builtin_commands(ctx);
    grn_db_init_builtin_window_functions(ctx);
    grn_db_init_builtin_token_filters(ctx);
    grn_db_init_builtin_aggregators(ctx);

    if (grn_table_size(ctx, (grn_obj *)s) > n_records) {
      need_flush = true;
    }
    if (need_flush) {
      grn_obj_flush(ctx, (grn_obj *)s);
    }
  }
  {
    uint32_t current_n_opening_dbs;
    GRN_ATOMIC_ADD_EX(&grn_n_opening_dbs, 1, current_n_opening_dbs);
  }
  grn_db_wal_recover(ctx, s);
  if (ctx->rc != GRN_SUCCESS) {
    grn_db_close(ctx, (grn_obj *)s);
    s = NULL;
    ctx->impl->db = NULL;
    goto exit;
  }
  GRN_API_RETURN((grn_obj *)s);

exit:
  if (s) {
    grn_options_close(ctx, s->options);
    if (s->config) {
      grn_hash_close(ctx, s->config);
    }
    if (s->specs) {
      grn_ja_close(ctx, s->specs);
    }
    if (s->keys) {
      if (s->keys->header.type == GRN_TABLE_PAT_KEY) {
        grn_pat_close(ctx, (grn_pat *)s->keys);
      } else {
        grn_dat_close(ctx, (grn_dat *)s->keys);
      }
    }
    grn_array_close(ctx, s->deferred_unrefs);
    grn_tiny_array_fin(&s->values);
    CRITICAL_SECTION_FIN(s->lock);
    GRN_FREE(s);
  }

  GRN_API_RETURN(NULL);
}

static grn_id
grn_db_curr_id(grn_ctx *ctx, grn_obj *db)
{
  grn_id curr_id = GRN_ID_NIL;
  grn_db *s = (grn_db *)db;
  switch (s->keys->header.type) {
  case GRN_TABLE_PAT_KEY:
    curr_id = grn_pat_curr_id(ctx, (grn_pat *)s->keys);
    break;
  case GRN_TABLE_DAT_KEY:
    curr_id = grn_dat_curr_id(ctx, (grn_dat *)s->keys);
    break;
  }
  return curr_id;
}

grn_rc
grn_db_add_deferred_unref(grn_ctx *ctx,
                          grn_obj *db,
                          grn_deferred_unref *deferred_unref)
{
  if (!grn_enable_reference_count) {
    return ctx->rc;
  }
  if (deferred_unref->count == 0) {
    return ctx->rc;
  }
  size_t n_ids = GRN_RECORD_VECTOR_SIZE(&(deferred_unref->ids));
  if (n_ids == 0) {
    return ctx->rc;
  }
  grn_db *db_ = (grn_db *)db;
  CRITICAL_SECTION_ENTER(db_->lock);
  void *value;
  grn_id id = grn_array_add(ctx, db_->deferred_unrefs, &value);
  if (id != GRN_ID_NIL) {
    grn_deferred_unref *value_deferred_unrefs = value;
    value_deferred_unrefs->count = deferred_unref->count;
    GRN_RECORD_INIT(&(value_deferred_unrefs->ids), GRN_OBJ_VECTOR, GRN_ID_NIL);
    /* Copy data */
    GRN_TEXT_SET(ctx,
                 &(value_deferred_unrefs->ids),
                 GRN_TEXT_VALUE(&(deferred_unref->ids)),
                 GRN_TEXT_LEN(&(deferred_unref->ids)));
  }
  CRITICAL_SECTION_LEAVE(db_->lock);
  return ctx->rc;
}

grn_rc
grn_db_remove_deferred_unref(grn_ctx *ctx, grn_obj *db, grn_id id)
{
  if (!grn_enable_reference_count) {
    return ctx->rc;
  }
  if (id == GRN_ID_NIL) {
    return ctx->rc;
  }
  grn_db *db_ = (grn_db *)db;
  if (db_->is_closing) {
    return ctx->rc;
  }
  if (db_->is_deferred_unrefing) {
    return ctx->rc;
  }
  CRITICAL_SECTION_ENTER(db_->lock);
  if (grn_array_size(ctx, db_->deferred_unrefs) > 0) {
    GRN_ARRAY_EACH_BEGIN(ctx,
                         db_->deferred_unrefs,
                         cursor,
                         GRN_ID_NIL,
                         GRN_ID_MAX,
                         id_)
    {
      void *value;
      grn_array_cursor_get_value(ctx, cursor, &value);
      grn_deferred_unref *deferred_unref = value;
      size_t n_ids = GRN_RECORD_VECTOR_SIZE(&(deferred_unref->ids));
      size_t i;
      for (i = 0; i < n_ids; i++) {
        if (GRN_RECORD_VALUE_AT(&(deferred_unref->ids), i) == id) {
          GRN_RECORD_VALUE_AT(&(deferred_unref->ids), i) = GRN_ID_NIL;
        }
      }
    }
    GRN_ARRAY_EACH_END(ctx, cursor);
  }
  CRITICAL_SECTION_LEAVE(db_->lock);
  return ctx->rc;
}

grn_rc
grn_db_command_processed(grn_ctx *ctx, grn_obj *db)
{
  if (!grn_enable_reference_count) {
    return ctx->rc;
  }

  grn_db *db_ = (grn_db *)db;
  CRITICAL_SECTION_ENTER(db_->lock);
  if (grn_array_size(ctx, db_->deferred_unrefs) > 0) {
    db_->is_deferred_unrefing = true;
    GRN_ARRAY_EACH_BEGIN(ctx,
                         db_->deferred_unrefs,
                         cursor,
                         GRN_ID_NIL,
                         GRN_ID_MAX,
                         id)
    {
      void *value;
      grn_array_cursor_get_value(ctx, cursor, &value);
      grn_deferred_unref *deferred_unref = value;
      deferred_unref->count--;
      if (deferred_unref->count == 0) {
        size_t n_ids = GRN_RECORD_VECTOR_SIZE(&(deferred_unref->ids));
        size_t i;
        for (i = 0; i < n_ids; i++) {
          grn_id deferred_id = GRN_RECORD_VALUE_AT(&(deferred_unref->ids), i);
          if (deferred_id == GRN_ID_NIL) {
            continue;
          }
          grn_obj *object = grn_ctx_at(ctx, deferred_id);
          if (object) {
            grn_obj_unref(ctx, object);
            grn_obj_unref(ctx, object);
          }
        }
        GRN_OBJ_FIN(ctx, &(deferred_unref->ids));
        grn_array_cursor_delete(ctx, cursor, NULL);
      }
    }
    GRN_ARRAY_EACH_END(ctx, cursor);
    db_->is_deferred_unrefing = false;
  }
  CRITICAL_SECTION_LEAVE(db_->lock);
  return ctx->rc;
}

/* db must be validated by caller */
grn_rc
grn_db_close(grn_ctx *ctx, grn_obj *db)
{
  grn_db *s = (grn_db *)db;
  if (!s) {
    return GRN_INVALID_ARGUMENT;
  }
  GRN_API_ENTER;

  s->is_closing = true;

  GRN_ARRAY_EACH_BEGIN(ctx,
                       s->deferred_unrefs,
                       cursor,
                       GRN_ID_NIL,
                       GRN_ID_MAX,
                       id)
  {
    void *value;
    grn_array_cursor_get_value(ctx, cursor, &value);
    grn_deferred_unref *deferred_unref = value;
    GRN_OBJ_FIN(ctx, &(deferred_unref->ids));
  }
  GRN_ARRAY_EACH_END(ctx, cursor);
  grn_array_close(ctx, s->deferred_unrefs);

  bool ctx_used_db = ctx->impl && ctx->impl->db == db;
  if (ctx_used_db) {
    grn_ctx_loader_clear(ctx);
    grn_ctx_expr_parsers_clear(ctx);
  }

  if (ctx_used_db) {
    if (ctx->impl->values) {
      grn_db_obj *o;
      GRN_ARRAY_EACH(ctx, ctx->impl->values, 0, 0, id, &o, {
        grn_obj_close(ctx, *((grn_obj **)o));
      });
      grn_array_truncate(ctx, ctx->impl->values);
    }
  }

  GRN_TINY_ARRAY_EACH_BEGIN(&s->values, 1, grn_db_curr_id(ctx, db), value)
  {
    db_value *vp = value;
    if (vp->ptr) {
      if (grn_obj_is_proc(ctx, vp->ptr) || grn_obj_is_table(ctx, vp->ptr)) {
        /* Defer */
      } else {
        switch (vp->ptr->header.type) {
        case GRN_COLUMN_FIX_SIZE:
          /* This is already closed by the above ctx->impl->values loop. */
          ((grn_ra *)(vp->ptr))->parsed_generator = NULL;
          break;
        case GRN_COLUMN_VAR_SIZE:
          /* This is already closed by the above ctx->impl->values loop. */
          ((grn_ja *)(vp->ptr))->parsed_generator = NULL;
          break;
        default:
          break;
        }
        grn_obj_close(ctx, vp->ptr);
      }
    }
  }
  GRN_TINY_ARRAY_EACH_END();
  GRN_TINY_ARRAY_EACH_BEGIN(&s->values, 1, grn_db_curr_id(ctx, db), value)
  {
    db_value *vp = value;
    if (vp->ptr) {
      if (grn_obj_is_proc(ctx, vp->ptr)) {
        /* Defer */
      } else {
        grn_obj_close(ctx, vp->ptr);
      }
    }
  }
  GRN_TINY_ARRAY_EACH_END();
  GRN_TINY_ARRAY_EACH_BEGIN(&s->values, 1, grn_db_curr_id(ctx, db), value)
  {
    db_value *vp = value;
    if (vp->ptr) {
      grn_obj_close(ctx, vp->ptr);
    }
  }
  GRN_TINY_ARRAY_EACH_END();
  grn_tiny_array_fin(&s->values);

  switch (s->keys->header.type) {
  case GRN_TABLE_PAT_KEY:
    grn_pat_close(ctx, (grn_pat *)s->keys);
    break;
  case GRN_TABLE_DAT_KEY:
    grn_dat_close(ctx, (grn_dat *)s->keys);
    break;
  }
  CRITICAL_SECTION_FIN(s->lock);
  if (s->specs) {
    grn_ja_close(ctx, s->specs);
  }
  grn_hash_close(ctx, s->config);
  grn_options_close(ctx, s->options);
  GRN_FREE(s);

  if (ctx_used_db) {
    ctx->impl->db = NULL;
  }

  {
    uint32_t current_n_opening_dbs;
    GRN_ATOMIC_ADD_EX(&grn_n_opening_dbs, -1, current_n_opening_dbs);
  }

  GRN_API_RETURN(GRN_SUCCESS);
}

grn_rc
grn_db_set_cache(grn_ctx *ctx, grn_obj *db, grn_cache *cache)
{
  GRN_API_ENTER;

  if (!ctx) {
    GRN_API_RETURN(GRN_INVALID_ARGUMENT);
  }

  if (!db) {
    ERR(GRN_INVALID_ARGUMENT, "[db][cache][set] DB must not NULL");
    GRN_API_RETURN(ctx->rc);
  }

  if (db->header.type != GRN_DB) {
    ERR(GRN_INVALID_ARGUMENT,
        "[db][cache][set] must be DB: %d",
        db->header.type);
    GRN_API_RETURN(ctx->rc);
  }

  ((grn_db *)db)->cache = cache;

  GRN_API_RETURN(GRN_SUCCESS);
}

grn_cache *
grn_db_get_cache(grn_ctx *ctx, grn_obj *db)
{
  grn_cache *cache;

  GRN_API_ENTER;

  if (!ctx) {
    GRN_API_RETURN(NULL);
  }

  if (!db) {
    ERR(GRN_INVALID_ARGUMENT, "[db][cache][get] DB must not NULL");
    GRN_API_RETURN(NULL);
  }

  if (db->header.type != GRN_DB) {
    ERR(GRN_INVALID_ARGUMENT,
        "[db][cache][get] must be DB: %d",
        db->header.type);
    GRN_API_RETURN(NULL);
  }

  cache = ((grn_db *)db)->cache;

  GRN_API_RETURN(cache);
}

static grn_obj *
grn_alias_resolve(grn_ctx *ctx,
                  const char *name,
                  int name_size,
                  grn_obj *alias_name_buffer,
                  grn_bool get_object)
{
  grn_db *db;
  grn_obj *alias_table = NULL;
  grn_obj *alias_column = NULL;

  db = (grn_db *)(ctx->impl->db);

  if (name_size < 0) {
    name_size = strlen(name);
  }

  while (GRN_TRUE) {
    if (get_object) {
      grn_id id;

      id = grn_table_get(ctx, db->keys, name, name_size);
      if (id) {
        return grn_ctx_at(ctx, id);
      }
    }

    if (!alias_column) {
      grn_id alias_column_id;
      const char *alias_column_name;
      uint32_t alias_column_name_size;

      grn_config_get(ctx,
                     "alias.column",
                     -1,
                     &alias_column_name,
                     &alias_column_name_size);
      if (!alias_column_name) {
        break;
      }
      alias_column_id =
        grn_table_get(ctx, db->keys, alias_column_name, alias_column_name_size);
      if (!alias_column_id) {
        break;
      }
      alias_column = grn_ctx_at(ctx, alias_column_id);
      if (alias_column->header.type != GRN_COLUMN_VAR_SIZE) {
        break;
      }
      if (alias_column->header.flags & GRN_OBJ_VECTOR) {
        break;
      }
      if (DB_OBJ(alias_column)->range != GRN_DB_SHORT_TEXT) {
        break;
      }
      alias_table = grn_ctx_at(ctx, alias_column->header.domain);
      if (alias_table->header.type == GRN_TABLE_NO_KEY) {
        break;
      }
    }

    {
      grn_id alias_id;
      alias_id = grn_table_get(ctx, alias_table, name, name_size);
      if (!alias_id) {
        break;
      }
      GRN_BULK_REWIND(alias_name_buffer);
      grn_obj_get_value(ctx, alias_column, alias_id, alias_name_buffer);
      name = GRN_TEXT_VALUE(alias_name_buffer);
      name_size = GRN_TEXT_LEN(alias_name_buffer);
    }
  }

  return NULL;
}

grn_obj *
grn_ctx_get(grn_ctx *ctx, const char *name, int name_size)
{
  grn_obj *obj = NULL;
  grn_obj *db;
  if (!ctx || !ctx->impl || !(db = ctx->impl->db)) {
    return NULL;
  }
  GRN_API_ENTER;
  if (GRN_DB_P(db)) {
    grn_obj alias_name_buffer;

    GRN_TEXT_INIT(&alias_name_buffer, 0);
    obj = grn_alias_resolve(ctx, name, name_size, &alias_name_buffer, GRN_TRUE);
    GRN_OBJ_FIN(ctx, &alias_name_buffer);
  }
  GRN_API_RETURN(obj);
}

grn_obj *
grn_ctx_db(grn_ctx *ctx)
{
  return (ctx && ctx->impl) ? ctx->impl->db : NULL;
}

grn_obj *
grn_db_keys(grn_obj *s)
{
  return (grn_obj *)(((grn_db *)s)->keys);
}

uint32_t
grn_obj_get_last_modified(grn_ctx *ctx, grn_obj *obj)
{
  if (!obj) {
    return 0;
  }

  return grn_obj_get_io(ctx, obj)->header->last_modified;
}

bool
grn_obj_is_dirty(grn_ctx *ctx, grn_obj *obj)
{
  if (!obj) {
    return false;
  }

  switch (obj->header.type) {
  case GRN_DB:
    return grn_db_is_dirty(ctx, obj);
  case GRN_TABLE_PAT_KEY:
    return grn_pat_is_dirty(ctx, (grn_pat *)obj);
  case GRN_TABLE_DAT_KEY:
    return grn_dat_is_dirty(ctx, (grn_dat *)obj);
  default:
    return false;
  }
}

uint32_t
grn_db_get_last_modified(grn_ctx *ctx, grn_obj *db)
{
  return grn_obj_get_last_modified(ctx, db);
}

bool
grn_db_is_dirty(grn_ctx *ctx, grn_obj *db)
{
  grn_obj *keys;

  if (!db) {
    return false;
  }

  keys = ((grn_db *)db)->keys;
  return grn_obj_is_dirty(ctx, keys);
}

static grn_rc
grn_db_dirty(grn_ctx *ctx, grn_obj *db)
{
  grn_obj *keys;

  if (!db) {
    return GRN_SUCCESS;
  }

  keys = ((grn_db *)db)->keys;
  switch (keys->header.type) {
  case GRN_TABLE_PAT_KEY:
    return grn_pat_dirty(ctx, (grn_pat *)keys);
  case GRN_TABLE_DAT_KEY:
    return grn_dat_dirty(ctx, (grn_dat *)keys);
  default:
    return GRN_SUCCESS;
  }
}

static grn_rc
grn_db_clean(grn_ctx *ctx, grn_obj *db)
{
  grn_obj *keys;

  if (!db) {
    return GRN_SUCCESS;
  }

  keys = ((grn_db *)db)->keys;
  switch (keys->header.type) {
  case GRN_TABLE_PAT_KEY:
    return grn_pat_clean(ctx, (grn_pat *)keys);
  case GRN_TABLE_DAT_KEY:
    return grn_dat_clean(ctx, (grn_dat *)keys);
  default:
    return GRN_SUCCESS;
  }
}

grn_rc
grn_db_clear_dirty(grn_ctx *ctx, grn_obj *db)
{
  grn_obj *keys;

  if (!db) {
    return GRN_SUCCESS;
  }

  keys = ((grn_db *)db)->keys;
  switch (keys->header.type) {
  case GRN_TABLE_PAT_KEY:
    return grn_pat_clear_dirty(ctx, (grn_pat *)keys);
  case GRN_TABLE_DAT_KEY:
    return grn_dat_clear_dirty(ctx, (grn_dat *)keys);
  default:
    return GRN_SUCCESS;
  }
}

void
grn_db_touch(grn_ctx *ctx, grn_obj *s)
{
  grn_obj_touch(ctx, s, NULL);
}

grn_bool
grn_obj_is_corrupt(grn_ctx *ctx, grn_obj *obj)
{
  bool is_corrupt = false;

  GRN_API_ENTER;

  if (!obj) {
    ERR(GRN_INVALID_ARGUMENT, "[object][corrupt] object must not be NULL");
    GRN_API_RETURN(GRN_FALSE);
  }

  switch (obj->header.type) {
  case GRN_DB:
    is_corrupt = grn_io_is_corrupt(ctx, grn_obj_get_io(ctx, obj));
    if (!is_corrupt) {
      is_corrupt = grn_io_is_corrupt(ctx, ((grn_db *)obj)->specs->io);
    }
    if (!is_corrupt) {
      is_corrupt = grn_io_is_corrupt(ctx, ((grn_db *)obj)->config->io);
    }
    if (!is_corrupt) {
      is_corrupt = grn_options_is_corrupt(ctx, ((grn_db *)obj)->options);
    }
    break;
  case GRN_TABLE_HASH_KEY:
  case GRN_TABLE_PAT_KEY:
    is_corrupt = grn_io_is_corrupt(ctx, grn_obj_get_io(ctx, obj));
    break;
  case GRN_TABLE_DAT_KEY:
    is_corrupt = grn_dat_is_corrupt(ctx, (grn_dat *)obj);
    break;
  case GRN_COLUMN_FIX_SIZE:
  case GRN_COLUMN_VAR_SIZE:
    is_corrupt = grn_io_is_corrupt(ctx, grn_obj_get_io(ctx, obj));
    break;
  case GRN_COLUMN_INDEX:
    is_corrupt = grn_io_is_corrupt(ctx, ((grn_ii *)obj)->seg);
    if (!is_corrupt) {
      is_corrupt = grn_io_is_corrupt(ctx, ((grn_ii *)obj)->chunk);
    }
    break;
  default:
    break;
  }

  GRN_API_RETURN(is_corrupt);
}

#define IS_TEMP(obj) (DB_OBJ(obj)->id & GRN_OBJ_TMP_OBJECT)

static inline void
grn_obj_touch_db(grn_ctx *ctx, grn_obj *obj, grn_timeval *tv)
{
  grn_obj_get_io(ctx, obj)->header->last_modified = (uint32_t)(tv->tv_sec);
  grn_db_dirty(ctx, obj);
}

void
grn_obj_touch(grn_ctx *ctx, grn_obj *obj, grn_timeval *tv)
{
  grn_timeval tv_;
  if (!tv) {
    grn_timeval_now(ctx, &tv_);
    tv = &tv_;
  }
  if (obj) {
    switch (obj->header.type) {
    case GRN_DB:
      grn_obj_touch_db(ctx, obj, tv);
      break;
    case GRN_TABLE_HASH_KEY:
    case GRN_TABLE_PAT_KEY:
    case GRN_TABLE_DAT_KEY:
    case GRN_TABLE_NO_KEY:
    case GRN_COLUMN_VAR_SIZE:
    case GRN_COLUMN_FIX_SIZE:
    case GRN_COLUMN_INDEX:
      if (!IS_TEMP(obj)) {
        grn_obj_get_io(ctx, obj)->header->last_modified =
          (uint32_t)(tv->tv_sec);
        grn_obj_touch(ctx, DB_OBJ(obj)->db, tv);
      }
      break;
    }
  }
}

grn_rc
grn_db_check_name(grn_ctx *ctx, const char *name, unsigned int name_size)
{
  int len;
  const char *name_end = name + name_size;
  if (name_size > 0 && *name == GRN_DB_PSEUDO_COLUMN_PREFIX) {
    return GRN_INVALID_ARGUMENT;
  }
  while (name < name_end) {
    char c = *name;
    if ((unsigned int)((c | 0x20) - 'a') >= 26u &&
        (unsigned int)(c - '0') >= 10u && c != '_' && c != '-' && c != '#' &&
        c != '@') {
      return GRN_INVALID_ARGUMENT;
    }
    if (!(len = grn_charlen(ctx, name, name_end))) {
      break;
    }
    name += len;
  }
  return GRN_SUCCESS;
}

grn_rc
grn_db_set_option_values(grn_ctx *ctx,
                         grn_obj *db,
                         grn_id id,
                         const char *name,
                         int name_length,
                         grn_obj *values)
{
  grn_db *db_ = (grn_db *)db;
  return grn_options_set(ctx, db_->options, id, name, name_length, values);
}

grn_option_revision
grn_db_get_option_values(grn_ctx *ctx,
                         grn_obj *db,
                         grn_id id,
                         const char *name,
                         int name_length,
                         grn_option_revision revision,
                         grn_obj *values)
{
  grn_db *db_ = (grn_db *)db;
  return grn_options_get(ctx,
                         db_->options,
                         id,
                         name,
                         name_length,
                         revision,
                         values);
}

grn_rc
grn_db_clear_option_values(grn_ctx *ctx, grn_obj *db, grn_id id)
{
  grn_db *db_ = (grn_db *)db;
  return grn_options_clear(ctx, db_->options, id);
}

static grn_obj *
grn_type_open(grn_ctx *ctx, grn_obj_spec *spec)
{
  struct _grn_type *res;
  res = GRN_MALLOC(sizeof(struct _grn_type));
  if (res) {
    GRN_DB_OBJ_SET_TYPE(res, GRN_TYPE);
    res->obj.header = spec->header;
    GRN_TYPE_SIZE(&res->obj) = GRN_TYPE_SIZE(spec);
  }
  return (grn_obj *)res;
}

grn_obj *
grn_proc_create(grn_ctx *ctx,
                const char *name,
                int name_size,
                grn_proc_type type,
                grn_proc_func *init,
                grn_proc_func *next,
                grn_proc_func *fin,
                unsigned int nvars,
                grn_expr_var *vars)
{
  grn_proc *res = NULL;
  grn_id id = GRN_ID_NIL;
  grn_id range = GRN_ID_NIL;
  int added = 0;
  grn_obj *db;
  const char *path;
  if (!ctx || !ctx->impl || !(db = ctx->impl->db)) {
    ERR(GRN_INVALID_ARGUMENT, "db not initialized");
    return NULL;
  }
  GRN_API_ENTER;
  path = ctx->impl->plugin_path;
  if (path) {
    range = grn_plugin_reference(ctx, path);
  }
  if (name_size < 0) {
    name_size = strlen(name);
  }
  if (grn_db_check_name(ctx, name, name_size)) {
    GRN_DB_CHECK_NAME_ERR("[proc][create]", name, name_size);
    GRN_API_RETURN(NULL);
  }
  if (!GRN_DB_P(db)) {
    ERR(GRN_INVALID_ARGUMENT, "invalid db assigned");
    GRN_API_RETURN(NULL);
  }
  if (name && name_size) {
    grn_db *s = (grn_db *)db;
    if (!(id = grn_table_get(ctx, s->keys, name, name_size))) {
      if (!(id = grn_table_add(ctx, s->keys, name, name_size, &added))) {
        ERR(GRN_NO_MEMORY_AVAILABLE, "grn_table_add failed");
        GRN_API_RETURN(NULL);
      }
    }
    if (!added) {
      db_value *vp;
      if ((vp = grn_tiny_array_at(&s->values, id)) &&
          (res = (grn_proc *)vp->ptr)) {
        /* TODO: Do more robust check. */
        if (res->funcs[PROC_INIT] || res->funcs[PROC_NEXT] ||
            res->funcs[PROC_FIN]) {
          ERR(GRN_INVALID_ARGUMENT,
              "[proc][create] already used name: <%.*s>",
              name_size,
              name);
          GRN_API_RETURN(NULL);
        }
        if (range != GRN_ID_NIL) {
          grn_plugin_close(ctx, range);
        }
        GRN_API_RETURN((grn_obj *)res);
      } else {
        added = 1;
      }
    }
  } else if (ctx->impl && ctx->impl->values) {
    id = grn_array_add(ctx, ctx->impl->values, NULL) | GRN_OBJ_TMP_OBJECT;
    added = 1;
  }
  if (!res) {
    res = GRN_MALLOCN(grn_proc, 1);
  }
  if (res) {
    GRN_DB_OBJ_SET_TYPE(res, GRN_PROC);
    res->obj.db = db;
    res->obj.id = id;
    res->obj.header.domain = GRN_ID_NIL;
    res->obj.header.flags = path ? GRN_OBJ_CUSTOM_NAME : 0;
    res->obj.range = range;
    res->type = type;
    res->funcs[PROC_INIT] = init;
    res->funcs[PROC_NEXT] = next;
    res->funcs[PROC_FIN] = fin;
    memset(&(res->callbacks), 0, sizeof(res->callbacks));
    if (type == GRN_PROC_FUNCTION) {
      res->callbacks.function.selector_op = GRN_OP_NOP;
      res->callbacks.function.is_stable = true;
    }
    GRN_TEXT_INIT(&res->name_buf, 0);
    res->vars = NULL;
    res->nvars = 0;
    if (added) {
      if (grn_db_obj_init(ctx, db, id, DB_OBJ(res))) {
        // grn_obj_delete(ctx, db, id);
        GRN_FREE(res);
        GRN_API_RETURN(NULL);
      }
    }
    while (nvars--) {
      grn_obj *v =
        grn_expr_add_var(ctx, (grn_obj *)res, vars->name, vars->name_size);
      if (!v) {
        grn_obj_close(ctx, (grn_obj *)res);
        GRN_API_RETURN(NULL);
      }
      GRN_OBJ_INIT(v, vars->value.header.type, 0, vars->value.header.domain);
      GRN_TEXT_PUT(ctx,
                   v,
                   GRN_TEXT_VALUE(&vars->value),
                   GRN_TEXT_LEN(&vars->value));
      vars++;
    }
  }
  GRN_API_RETURN((grn_obj *)res);
}

/* grn_table */

static void
calc_rec_size(grn_table_flags flags,
              uint32_t max_n_subrecs,
              uint32_t range_size,
              uint32_t additional_value_size,
              uint8_t *subrec_size,
              uint8_t *subrec_offset,
              uint32_t *key_size,
              uint32_t *value_size)
{
  *subrec_size = 0;
  *subrec_offset = 0;
  if (flags & GRN_OBJ_WITH_SUBREC) {
    switch (flags & GRN_OBJ_UNIT_MASK) {
    case GRN_OBJ_UNIT_DOCUMENT_NONE:
      break;
    case GRN_OBJ_UNIT_DOCUMENT_SECTION:
      *subrec_offset = sizeof(grn_id);
      *subrec_size = sizeof(uint32_t);
      break;
    case GRN_OBJ_UNIT_DOCUMENT_POSITION:
      *subrec_offset = sizeof(grn_id);
      *subrec_size = sizeof(uint32_t) + sizeof(uint32_t);
      break;
    case GRN_OBJ_UNIT_SECTION_NONE:
      *key_size += sizeof(uint32_t);
      break;
    case GRN_OBJ_UNIT_SECTION_POSITION:
      *key_size += sizeof(uint32_t);
      *subrec_offset = sizeof(grn_id) + sizeof(uint32_t);
      *subrec_size = sizeof(uint32_t);
      break;
    case GRN_OBJ_UNIT_POSITION_NONE:
      *key_size += sizeof(uint32_t) + sizeof(uint32_t);
      break;
    case GRN_OBJ_UNIT_USERDEF_DOCUMENT:
      *subrec_size = range_size;
      break;
    case GRN_OBJ_UNIT_USERDEF_SECTION:
      *subrec_size = range_size + sizeof(uint32_t);
      break;
    case GRN_OBJ_UNIT_USERDEF_POSITION:
      *subrec_size = range_size + sizeof(uint32_t) + sizeof(uint32_t);
      break;
    }
    *value_size =
      (uintptr_t)GRN_RSET_SUBRECS_NTH((((grn_rset_recinfo *)0)->subrecs),
                                      *subrec_size,
                                      max_n_subrecs);
  } else {
    *value_size = range_size;
  }
  *value_size += additional_value_size;
}

static grn_rc
grn_obj_remove_internal(grn_ctx *ctx, grn_obj *obj, uint32_t flags);

static grn_rc
grn_table_create_validate(grn_ctx *ctx,
                          const char *name,
                          unsigned int name_size,
                          const char *path,
                          grn_table_flags flags,
                          grn_obj *key_type,
                          grn_obj *value_type)
{
  grn_table_flags table_type;
  const char *table_type_name = NULL;

  table_type = (flags & GRN_OBJ_TABLE_TYPE_MASK);
  switch (table_type) {
  case GRN_OBJ_TABLE_HASH_KEY:
    table_type_name = "TABLE_HASH_KEY";
    break;
  case GRN_OBJ_TABLE_PAT_KEY:
    table_type_name = "TABLE_PAT_KEY";
    break;
  case GRN_OBJ_TABLE_DAT_KEY:
    table_type_name = "TABLE_DAT_KEY";
    break;
  case GRN_OBJ_TABLE_NO_KEY:
    table_type_name = "TABLE_NO_KEY";
    break;
  default:
    table_type_name = "unknown";
    break;
  }

  if (!key_type && table_type != GRN_OBJ_TABLE_NO_KEY &&
      !(flags & GRN_OBJ_KEY_VAR_SIZE)) {
    ERR(GRN_INVALID_ARGUMENT,
        "[table][create] "
        "key type is required for TABLE_HASH_KEY, TABLE_PAT_KEY or "
        "TABLE_DAT_KEY: <%.*s>",
        name_size,
        name);
    return ctx->rc;
  }

  if (key_type && table_type == GRN_OBJ_TABLE_NO_KEY) {
    int key_name_size;
    char key_name[GRN_TABLE_MAX_KEY_SIZE];
    key_name_size =
      grn_obj_name(ctx, key_type, key_name, GRN_TABLE_MAX_KEY_SIZE);
    ERR(GRN_INVALID_ARGUMENT,
        "[table][create] "
        "key isn't available for TABLE_NO_KEY table: <%.*s> (%.*s)",
        name_size,
        name,
        key_name_size,
        key_name);
    return ctx->rc;
  }

  if ((flags & GRN_OBJ_KEY_WITH_SIS) && table_type != GRN_OBJ_TABLE_PAT_KEY) {
    ERR(GRN_INVALID_ARGUMENT,
        "[table][create] "
        "key with SIS is available only for TABLE_PAT_KEY table: "
        "<%.*s>(%s)",
        name_size,
        name,
        table_type_name);
    return ctx->rc;
  }

  if ((flags & GRN_OBJ_KEY_NORMALIZE) && table_type == GRN_OBJ_TABLE_NO_KEY) {
    ERR(GRN_INVALID_ARGUMENT,
        "[table][create] "
        "key normalization isn't available for TABLE_NO_KEY table: <%.*s>",
        name_size,
        name);
    return ctx->rc;
  }

  if ((flags & GRN_OBJ_KEY_LARGE) && table_type != GRN_OBJ_TABLE_HASH_KEY) {
    ERR(GRN_INVALID_ARGUMENT,
        "[table][create] "
        "large key support is available only for TABLE_HASH_KEY key table: "
        "<%.*s>(%s)",
        name_size,
        name,
        table_type_name);
    return ctx->rc;
  }

  return ctx->rc;
}

grn_obj *
grn_table_create_with_max_n_subrecs(grn_ctx *ctx,
                                    const char *name,
                                    unsigned int name_size,
                                    const char *path,
                                    grn_table_flags flags,
                                    grn_obj *key_type,
                                    grn_obj *value_type,
                                    uint32_t max_n_subrecs,
                                    uint32_t additional_value_size)
{
  grn_id id;
  grn_id domain = GRN_ID_NIL, range = GRN_ID_NIL;
  uint32_t key_size, value_size = 0, range_size = 0;
  uint8_t subrec_size, subrec_offset;
  grn_obj *res = NULL;
  grn_obj *db;
  char buffer[PATH_MAX];
  if (!ctx->impl || !(db = ctx->impl->db)) {
    ERR(GRN_INVALID_ARGUMENT, "[table][create] db not initialized");
    return NULL;
  }
  if (grn_db_check_name(ctx, name, name_size)) {
    GRN_DB_CHECK_NAME_ERR("[table][create]", name, name_size);
    return NULL;
  }
  if (!GRN_DB_P(db)) {
    ERR(GRN_INVALID_ARGUMENT, "[table][create] invalid db assigned");
    return NULL;
  }
  if (grn_table_create_validate(ctx,
                                name,
                                name_size,
                                path,
                                flags,
                                key_type,
                                value_type)) {
    return NULL;
  }
  if (key_type) {
    domain = DB_OBJ(key_type)->id;
    switch (key_type->header.type) {
    case GRN_TYPE:
      {
        grn_db_obj *t = (grn_db_obj *)key_type;
        flags |= t->header.flags;
        key_size = GRN_TYPE_SIZE(t);
        if (key_size > GRN_TABLE_MAX_KEY_SIZE) {
          int type_name_size;
          char type_name[GRN_TABLE_MAX_KEY_SIZE];
          type_name_size =
            grn_obj_name(ctx, key_type, type_name, GRN_TABLE_MAX_KEY_SIZE);
          ERR(GRN_INVALID_ARGUMENT,
              "[table][create] key size too big: <%.*s> <%.*s>(%u) (max:%u)",
              name_size,
              name,
              type_name_size,
              type_name,
              key_size,
              GRN_TABLE_MAX_KEY_SIZE);
          return NULL;
        }
      }
      break;
    case GRN_TABLE_HASH_KEY:
    case GRN_TABLE_PAT_KEY:
    case GRN_TABLE_DAT_KEY:
    case GRN_TABLE_NO_KEY:
      key_size = sizeof(grn_id);
      break;
    default:
      {
        int key_name_size;
        char key_name[GRN_TABLE_MAX_KEY_SIZE];
        key_name_size =
          grn_obj_name(ctx, key_type, key_name, GRN_TABLE_MAX_KEY_SIZE);
        ERR(GRN_INVALID_ARGUMENT,
            "[table][create] key type must be type or table: <%.*s> (%.*s)",
            name_size,
            name,
            key_name_size,
            key_name);
        return NULL;
      }
      break;
    }
  } else {
    key_size =
      (flags & GRN_OBJ_KEY_VAR_SIZE) ? GRN_TABLE_MAX_KEY_SIZE : sizeof(grn_id);
  }
  if (value_type) {
    range = DB_OBJ(value_type)->id;
    switch (value_type->header.type) {
    case GRN_TYPE:
      {
        grn_db_obj *t = (grn_db_obj *)value_type;
        if (t->header.flags & GRN_OBJ_KEY_VAR_SIZE) {
          int type_name_size;
          char type_name[GRN_TABLE_MAX_KEY_SIZE];
          type_name_size =
            grn_obj_name(ctx, value_type, type_name, GRN_TABLE_MAX_KEY_SIZE);
          ERR(GRN_INVALID_ARGUMENT,
              "[table][create] value type must be fixed size: <%.*s> (%.*s)",
              name_size,
              name,
              type_name_size,
              type_name);
          return NULL;
        }
        range_size = GRN_TYPE_SIZE(t);
      }
      break;
    case GRN_TABLE_HASH_KEY:
    case GRN_TABLE_PAT_KEY:
    case GRN_TABLE_DAT_KEY:
    case GRN_TABLE_NO_KEY:
      range_size = sizeof(grn_id);
      break;
    default:
      {
        int value_name_size;
        char value_name[GRN_TABLE_MAX_KEY_SIZE];
        value_name_size =
          grn_obj_name(ctx, value_type, value_name, GRN_TABLE_MAX_KEY_SIZE);
        ERR(GRN_INVALID_ARGUMENT,
            "[table][create] value type must be type or table: <%.*s> (%.*s)",
            name_size,
            name,
            value_name_size,
            value_name);
        return NULL;
      }
      break;
    }
  }

  id = grn_obj_register(ctx, db, name, name_size);
  if (ERRP(ctx, GRN_ERROR)) {
    return NULL;
  }
  if (GRN_OBJ_PERSISTENT & flags) {
    GRN_LOG(ctx,
            GRN_LOG_NOTICE,
            "DDL:%u:table_create %.*s",
            id,
            name_size,
            name);
    if (!path) {
      if (GRN_DB_PERSISTENT_P(db)) {
        grn_db_generate_pathname(ctx, db, id, buffer);
        path = buffer;
      } else {
        ERR(GRN_INVALID_ARGUMENT, "path not assigned for persistent table");
        grn_obj_delete_by_id(ctx, db, id, GRN_TRUE);
        return NULL;
      }
    } else {
      flags |= GRN_OBJ_CUSTOM_NAME;
    }
  } else {
    if (path) {
      ERR(GRN_INVALID_ARGUMENT, "path assigned for temporary table");
      grn_obj_delete_by_id(ctx, db, id, GRN_TRUE);
      return NULL;
    }
    if (GRN_DB_PERSISTENT_P(db) && name && name_size) {
      ERR(GRN_INVALID_ARGUMENT, "name assigned for temporary table");
      grn_obj_delete_by_id(ctx, db, id, GRN_TRUE);
      return NULL;
    }
  }
  calc_rec_size(flags,
                max_n_subrecs,
                range_size,
                additional_value_size,
                &subrec_size,
                &subrec_offset,
                &key_size,
                &value_size);
  switch (flags & GRN_OBJ_TABLE_TYPE_MASK) {
  case GRN_OBJ_TABLE_HASH_KEY:
    res = (grn_obj *)grn_hash_create(ctx, path, key_size, value_size, flags);
    break;
  case GRN_OBJ_TABLE_PAT_KEY:
    res = (grn_obj *)grn_pat_create(ctx, path, key_size, value_size, flags);
    break;
  case GRN_OBJ_TABLE_DAT_KEY:
    res = (grn_obj *)grn_dat_create(ctx, path, key_size, value_size, flags);
    break;
  case GRN_OBJ_TABLE_NO_KEY:
    domain = range;
    res = (grn_obj *)grn_array_create(ctx, path, value_size, flags);
    break;
  }
  if (res) {
    DB_OBJ(res)->header.impl_flags = 0;
    DB_OBJ(res)->header.domain = domain;
    DB_OBJ(res)->range = range;
    DB_OBJ(res)->max_n_subrecs = max_n_subrecs;
    DB_OBJ(res)->subrec_size = subrec_size;
    DB_OBJ(res)->subrec_offset = subrec_offset;
    DB_OBJ(res)->group.flags = 0;
    DB_OBJ(res)->group.calc_target = NULL;
    DB_OBJ(res)->group.aggregated_value_type_id = GRN_DB_INT64;
    if (grn_db_obj_init(ctx, db, id, DB_OBJ(res)) == GRN_SUCCESS) {
      if (grn_obj_is_persistent(ctx, res)) {
        grn_obj *space;
        space = ctx->impl->temporary_open_spaces.current;
        if (space) {
          GRN_PTR_PUT(ctx, space, res);
        }
      }
    } else {
      grn_obj_remove_internal(ctx, res, 0);
      res = NULL;
    }
  } else {
    grn_obj_delete_by_id(ctx, db, id, GRN_TRUE);
  }
  return res;
}

grn_obj *
grn_table_create(grn_ctx *ctx,
                 const char *name,
                 unsigned int name_size,
                 const char *path,
                 grn_table_flags flags,
                 grn_obj *key_type,
                 grn_obj *value_type)
{
  grn_obj *res;
  GRN_API_ENTER;
  res = grn_table_create_with_max_n_subrecs(ctx,
                                            name,
                                            name_size,
                                            path,
                                            flags,
                                            key_type,
                                            value_type,
                                            0,
                                            0);
  GRN_API_RETURN(res);
}

grn_obj *
grn_table_create_for_group(grn_ctx *ctx,
                           const char *name,
                           unsigned int name_size,
                           const char *path,
                           grn_obj *group_key,
                           grn_obj *value_type,
                           uint32_t max_n_subrecs)
{
  grn_obj *res = NULL;
  GRN_API_ENTER;
  if (group_key) {
    grn_obj *key_type;
    key_type = grn_ctx_at(ctx, grn_obj_get_range(ctx, group_key));
    if (key_type) {
      res = grn_table_create_with_max_n_subrecs(ctx,
                                                name,
                                                name_size,
                                                path,
                                                GRN_OBJ_TABLE_HASH_KEY |
                                                  GRN_OBJ_WITH_SUBREC |
                                                  GRN_OBJ_UNIT_USERDEF_DOCUMENT,
                                                key_type,
                                                value_type,
                                                max_n_subrecs,
                                                0);
      grn_obj_unlink(ctx, key_type);
    }
  } else {
    res = grn_table_create_with_max_n_subrecs(
      ctx,
      name,
      name_size,
      path,
      GRN_OBJ_TABLE_HASH_KEY | GRN_OBJ_KEY_VAR_SIZE | GRN_OBJ_WITH_SUBREC |
        GRN_OBJ_UNIT_USERDEF_DOCUMENT,
      NULL,
      value_type,
      max_n_subrecs,
      0);
  }
  GRN_API_RETURN(res);
}

grn_obj *
grn_table_create_similar(grn_ctx *ctx,
                         const char *name,
                         uint32_t name_size,
                         const char *path,
                         grn_obj *base_table)
{
  GRN_API_ENTER;
  grn_obj *table = grn_table_create_similar_id_map(ctx,
                                                   name,
                                                   name_size,
                                                   path,
                                                   base_table,
                                                   NULL);
  GRN_API_RETURN(table);
}

unsigned int
grn_table_get_subrecs(grn_ctx *ctx,
                      grn_obj *table,
                      grn_id id,
                      grn_id *subrecbuf,
                      int *scorebuf,
                      int buf_size)
{
  unsigned int count = 0;
  GRN_API_ENTER;
  if (GRN_OBJ_TABLEP(table)) {
    uint32_t value_size;
    grn_rset_recinfo *ri;
    uint32_t subrec_size = DB_OBJ(table)->subrec_size;
    uint32_t max_n_subrecs = DB_OBJ(table)->max_n_subrecs;
    if (subrec_size < sizeof(grn_id)) {
      goto exit;
    }
    if (!max_n_subrecs) {
      goto exit;
    }
    ri = (grn_rset_recinfo *)grn_obj_get_value_(ctx, table, id, &value_size);
    if (ri) {
      byte *psubrec = (byte *)ri->subrecs;
      uint32_t n_subrecs = (uint32_t)GRN_RSET_N_SUBRECS(ri);
      uint32_t limit = value_size / (GRN_RSET_SCORE_SIZE + subrec_size);
      if ((int)limit > buf_size) {
        limit = buf_size;
      }
      if (limit > n_subrecs) {
        limit = n_subrecs;
      }
      if (limit > max_n_subrecs) {
        limit = max_n_subrecs;
      }
      for (; count < limit; count++) {
        if (scorebuf) {
          scorebuf[count] = *((double *)psubrec);
        }
        psubrec += GRN_RSET_SCORE_SIZE;
        if (subrecbuf) {
          subrecbuf[count] = *((grn_id *)psubrec);
        }
        psubrec += subrec_size;
      }
    }
  }
exit:
  GRN_API_RETURN(count);
}

grn_obj *
grn_table_open(grn_ctx *ctx,
               const char *name,
               unsigned int name_size,
               const char *path)
{
  grn_obj *db;
  if (!ctx->impl || !(db = ctx->impl->db)) {
    ERR(GRN_INVALID_ARGUMENT, "db not initialized");
    return NULL;
  }
  GRN_API_ENTER;
  if (!GRN_DB_P(db)) {
    ERR(GRN_INVALID_ARGUMENT, "invalid db assigned");
    GRN_API_RETURN(NULL);
  } else {
    grn_obj *res = grn_ctx_get(ctx, name, name_size);
    if (res) {
      const char *path2 = grn_obj_path(ctx, res);
      if (path && (!path2 || strcmp(path, path2))) {
        ERR(GRN_INVALID_ARGUMENT, "path unmatch");
        GRN_API_RETURN(NULL);
      }
    } else if (path) {
      uint32_t type = grn_io_detect_type(ctx, path);
      if (!type) {
        GRN_API_RETURN(NULL);
      }
      switch (type) {
      case GRN_TABLE_HASH_KEY:
        res = (grn_obj *)grn_hash_open(ctx, path);
        break;
      case GRN_TABLE_PAT_KEY:
        res = (grn_obj *)grn_pat_open(ctx, path);
        break;
      case GRN_TABLE_DAT_KEY:
        res = (grn_obj *)grn_dat_open(ctx, path);
        break;
      case GRN_TABLE_NO_KEY:
        res = (grn_obj *)grn_array_open(ctx, path);
        break;
      }
      if (res) {
        grn_id id = grn_obj_register(ctx, db, name, name_size);
        res->header.flags |= GRN_OBJ_CUSTOM_NAME;
        res->header.domain = GRN_ID_NIL; /* unknown */
        DB_OBJ(res)->range = GRN_ID_NIL; /* unknown */
        grn_db_obj_init(ctx, db, id, DB_OBJ(res));
      }
    } else {
      ERR(GRN_INVALID_ARGUMENT, "path is missing");
    }
    GRN_API_RETURN(res);
  }
}

grn_id
grn_table_lcp_search(grn_ctx *ctx,
                     grn_obj *table,
                     const void *key,
                     unsigned int key_size)
{
  grn_id id = GRN_ID_NIL;
  GRN_API_ENTER;
  switch (table->header.type) {
  case GRN_TABLE_PAT_KEY:
    {
      grn_pat *pat = (grn_pat *)table;
      WITH_NORMALIZE(pat, key, key_size, {
        id = grn_pat_lcp_search(ctx, pat, key, key_size);
      });
    }
    break;
  case GRN_TABLE_DAT_KEY:
    {
      grn_dat *dat = (grn_dat *)table;
      WITH_NORMALIZE(dat, key, key_size, {
        id = grn_dat_lcp_search(ctx, dat, key, key_size);
      });
    }
    break;
  case GRN_TABLE_HASH_KEY:
    {
      grn_hash *hash = (grn_hash *)table;
      WITH_NORMALIZE(hash, key, key_size, {
        id = grn_hash_get(ctx, hash, key, key_size, NULL);
      });
    }
    break;
  }
  GRN_API_RETURN(id);
}

grn_obj *
grn_obj_default_set_value_hook(grn_ctx *ctx,
                               int nargs,
                               grn_obj **args,
                               grn_user_data *user_data)
{
  grn_proc_ctx *pctx = (grn_proc_ctx *)user_data;
  if (!pctx) {
    ERR(GRN_INVALID_ARGUMENT, "default_set_value_hook failed");
  } else {
    grn_obj *flags = grn_ctx_pop(ctx);
    grn_obj *newvalue = grn_ctx_pop(ctx);
    grn_obj *oldvalue = grn_ctx_pop(ctx);
    grn_obj *id = grn_ctx_pop(ctx);
    grn_hook *h = pctx->currh;
    grn_obj_default_set_value_hook_data *data = (void *)GRN_NEXT_ADDR(h);
    grn_obj *target = grn_ctx_at(ctx, data->target);
    int section = data->section;
    if (flags) { /* todo */
    }
    if (target) {
      switch (target->header.type) {
      case GRN_COLUMN_FIX_SIZE:
        if (((grn_ra *)target)->generator.length > 0) {
          grn_generated_column_update(ctx,
                                      target,
                                      GRN_UINT32_VALUE(id),
                                      section,
                                      oldvalue,
                                      newvalue);
        }
        break;
      case GRN_COLUMN_VAR_SIZE:
        if (((grn_ja *)target)->generator.length > 0) {
          grn_generated_column_update(ctx,
                                      target,
                                      GRN_UINT32_VALUE(id),
                                      section,
                                      oldvalue,
                                      newvalue);
        } else {
          grn_token_column_update(ctx,
                                  target,
                                  GRN_UINT32_VALUE(id),
                                  section,
                                  oldvalue,
                                  newvalue);
        }
        break;
      case GRN_COLUMN_INDEX:
        grn_ii_column_update(ctx,
                             (grn_ii *)target,
                             GRN_UINT32_VALUE(id),
                             section,
                             oldvalue,
                             newvalue,
                             NULL);
        break;
      default:
        break;
      }
      grn_obj_unref(ctx, target);
    }
  }
  return NULL;
}

static grn_id
grn_table_add_internal(grn_ctx *ctx,
                       grn_obj *table,
                       const void *key,
                       unsigned int key_size,
                       grn_table_add_options *options)
{
  grn_id id = GRN_ID_NIL;
  GRN_API_ENTER;
  if (table) {
    grn_table_add_options local_options = {0};
    if (!options) {
      options = &local_options;
    }
    switch (table->header.type) {
    case GRN_TABLE_PAT_KEY:
      {
        grn_pat *pat = (grn_pat *)table;
        WITH_NORMALIZE(pat, key, key_size, {
          if (key_size == 0 && options->ignore_empty_normalized_key) {
            options->ignored = true;
          } else {
            GRN_TABLE_LOCK_BEGIN(ctx, table)
            {
              int added = 0;
              id = grn_pat_add(ctx, pat, key, key_size, NULL, &added);
              options->added = added;
            }
            GRN_TABLE_LOCK_END(ctx);
          }
        });
        if (id == GRN_ID_NIL && !options->ignored) {
          grn_obj buffer;
          GRN_TEXT_INIT(&buffer, 0);
          grn_inspect_key(ctx, &buffer, table, key, key_size);
          ERR(GRN_INVALID_ARGUMENT,
              "[table][add][pat] failed to add: %.*s",
              (int)GRN_TEXT_LEN(&buffer),
              GRN_TEXT_VALUE(&buffer));
          GRN_OBJ_FIN(ctx, &buffer);
        }
      }
      break;
    case GRN_TABLE_DAT_KEY:
      {
        grn_dat *dat = (grn_dat *)table;
        WITH_NORMALIZE(dat, key, key_size, {
          if (key_size == 0 && options->ignore_empty_normalized_key) {
            options->ignored = true;
          } else {
            GRN_TABLE_LOCK_BEGIN(ctx, table)
            {
              int added = 0;
              id = grn_dat_add(ctx, dat, key, key_size, NULL, &added);
              options->added = added;
            }
            GRN_TABLE_LOCK_END(ctx);
          }
        });
        if (id == GRN_ID_NIL && !options->ignored) {
          grn_obj buffer;
          GRN_TEXT_INIT(&buffer, 0);
          grn_inspect_key(ctx, &buffer, table, key, key_size);
          ERR(GRN_INVALID_ARGUMENT,
              "[table][add][dat] failed to add: %.*s",
              (int)GRN_TEXT_LEN(&buffer),
              GRN_TEXT_VALUE(&buffer));
          GRN_OBJ_FIN(ctx, &buffer);
        }
      }
      break;
    case GRN_TABLE_HASH_KEY:
      {
        grn_hash *hash = (grn_hash *)table;
        WITH_NORMALIZE(hash, key, key_size, {
          if (key_size == 0 && options->ignore_empty_normalized_key) {
            options->ignored = true;
          } else {
            GRN_TABLE_LOCK_BEGIN(ctx, table)
            {
              int added;
              id = grn_hash_add(ctx, hash, key, key_size, NULL, &added);
              options->added = added;
            }
            GRN_TABLE_LOCK_END(ctx);
          }
        });
        if (id == GRN_ID_NIL && !options->ignored) {
          grn_obj buffer;
          GRN_TEXT_INIT(&buffer, 0);
          grn_inspect_key(ctx, &buffer, table, key, key_size);
          ERR(GRN_INVALID_ARGUMENT,
              "[table][add][hash] failed to add: %.*s",
              (int)GRN_TEXT_LEN(&buffer),
              GRN_TEXT_VALUE(&buffer));
          GRN_OBJ_FIN(ctx, &buffer);
        }
      }
      break;
    case GRN_TABLE_NO_KEY:
      {
        grn_array *array = (grn_array *)table;
        GRN_TABLE_LOCK_BEGIN(ctx, table)
        {
          id = grn_array_add(ctx, array, NULL);
        }
        GRN_TABLE_LOCK_END(ctx);
        options->added = (id != GRN_ID_NIL);
        if (id == GRN_ID_NIL) {
          grn_obj buffer;
          GRN_TEXT_INIT(&buffer, 0);
          grn_inspect_key(ctx, &buffer, table, key, key_size);
          ERR(GRN_INVALID_ARGUMENT,
              "[table][add][array] failed to add: %.*s",
              (int)GRN_TEXT_LEN(&buffer),
              GRN_TEXT_VALUE(&buffer));
          GRN_OBJ_FIN(ctx, &buffer);
        }
      }
      break;
    }
    if (options->added) {
      grn_hook *hooks = DB_OBJ(table)->hooks[GRN_HOOK_INSERT];
      if (hooks) {
        // todo : grn_proc_ctx_open()
        grn_obj id_, flags_, oldvalue_, value_;
        grn_proc_ctx pctx;
        grn_proc_ctx_init(&pctx, hooks, 4, 4);
        GRN_UINT32_INIT(&id_, 0);
        GRN_UINT32_INIT(&flags_, 0);
        GRN_VOID_INIT(&oldvalue_);
        grn_obj_reinit_for(ctx, &oldvalue_, table);
        GRN_OBJ_INIT(&value_,
                     GRN_BULK,
                     GRN_OBJ_DO_SHALLOW_COPY,
                     table->header.domain);
        GRN_TEXT_SET_REF(&value_, key, key_size);
        GRN_UINT32_SET(ctx, &id_, id);
        GRN_UINT32_SET(ctx, &flags_, GRN_OBJ_SET);
        while (hooks) {
          grn_ctx_push(ctx, &id_);
          grn_ctx_push(ctx, &oldvalue_);
          grn_ctx_push(ctx, &value_);
          grn_ctx_push(ctx, &flags_);
          pctx.caller = NULL;
          pctx.currh = hooks;
          if (hooks->proc) {
            hooks->proc->funcs[PROC_INIT](ctx, 1, &table, &pctx.user_data);
          } else {
            grn_obj_default_set_value_hook(ctx, 1, &table, &pctx.user_data);
          }
          if (ctx->rc) {
            break;
          }
          hooks = hooks->next;
          pctx.offset++;
        }
        GRN_OBJ_FIN(ctx, &id_);
        GRN_OBJ_FIN(ctx, &flags_);
        GRN_OBJ_FIN(ctx, &oldvalue_);
        GRN_OBJ_FIN(ctx, &value_);
      }
    }
  } else {
    ERR(GRN_INVALID_ARGUMENT,
        "[table][add] failed to add: table must not NULL");
  }
  GRN_API_RETURN(id);
}

grn_id
grn_table_add(grn_ctx *ctx,
              grn_obj *table,
              const void *key,
              unsigned int key_size,
              int *added)
{
  grn_table_add_options options = {0};
  grn_id id = grn_table_add_internal(ctx, table, key, key_size, &options);
  if (added) {
    *added = options.added ? 1 : 0;
  }
  return id;
}

grn_id
grn_table_get_by_key(grn_ctx *ctx, grn_obj *table, grn_obj *key)
{
  grn_id id = GRN_ID_NIL;
  if (grn_type_id_is_compatible(ctx,
                                table->header.domain,
                                key->header.domain)) {
    id = grn_table_get(ctx, table, GRN_TEXT_VALUE(key), GRN_TEXT_LEN(key));
  } else {
    grn_rc rc;
    grn_obj buf;
    GRN_OBJ_INIT(&buf, GRN_BULK, 0, table->header.domain);
    if ((rc = grn_obj_cast(ctx, key, &buf, GRN_TRUE))) {
      grn_obj *domain = grn_ctx_at(ctx, table->header.domain);
      ERR_CAST(table, domain, key);
    } else {
      id = grn_table_get(ctx, table, GRN_TEXT_VALUE(&buf), GRN_TEXT_LEN(&buf));
    }
    GRN_OBJ_FIN(ctx, &buf);
  }
  return id;
}

grn_id
grn_table_add_by_key(grn_ctx *ctx,
                     grn_obj *table,
                     grn_obj *key,
                     grn_table_add_options *options)
{
  grn_id id = GRN_ID_NIL;
  if (grn_type_id_is_compatible(ctx,
                                table->header.domain,
                                key->header.domain)) {
    id = grn_table_add_internal(ctx,
                                table,
                                GRN_TEXT_VALUE(key),
                                GRN_TEXT_LEN(key),
                                options);
  } else {
    grn_rc rc;
    grn_obj buf;
    GRN_OBJ_INIT(&buf, GRN_BULK, 0, table->header.domain);
    if ((rc = grn_obj_cast(ctx, key, &buf, GRN_TRUE))) {
      grn_obj *domain = grn_ctx_at(ctx, table->header.domain);
      ERR_CAST(table, domain, key);
    } else {
      id = grn_table_add_internal(ctx,
                                  table,
                                  GRN_TEXT_VALUE(&buf),
                                  GRN_TEXT_LEN(&buf),
                                  options);
    }
    GRN_OBJ_FIN(ctx, &buf);
  }
  return id;
}

grn_id
grn_table_get(grn_ctx *ctx,
              grn_obj *table,
              const void *key,
              unsigned int key_size)
{
  grn_id id = GRN_ID_NIL;
  GRN_API_ENTER;
  if (table) {
    if (table->header.type == GRN_DB) {
      grn_db *db = (grn_db *)table;
      table = db->keys;
    }
    switch (table->header.type) {
    case GRN_TABLE_PAT_KEY:
      WITH_NORMALIZE((grn_pat *)table, key, key_size, {
        id = grn_pat_get(ctx, (grn_pat *)table, key, key_size, NULL);
      });
      break;
    case GRN_TABLE_DAT_KEY:
      WITH_NORMALIZE((grn_dat *)table, key, key_size, {
        id = grn_dat_get(ctx, (grn_dat *)table, key, key_size, NULL);
      });
      break;
    case GRN_TABLE_HASH_KEY:
      WITH_NORMALIZE((grn_hash *)table, key, key_size, {
        id = grn_hash_get(ctx, (grn_hash *)table, key, key_size, NULL);
      });
      break;
    }
  }
  GRN_API_RETURN(id);
}

grn_id
grn_table_at(grn_ctx *ctx, grn_obj *table, grn_id id)
{
  GRN_API_ENTER;
  if (table) {
    switch (table->header.type) {
    case GRN_DB:
      {
        grn_db *db = (grn_db *)table;
        id = grn_table_at(ctx, db->keys, id);
      }
      break;
    case GRN_TABLE_PAT_KEY:
      id = grn_pat_at(ctx, (grn_pat *)table, id);
      break;
    case GRN_TABLE_DAT_KEY:
      id = grn_dat_at(ctx, (grn_dat *)table, id);
      break;
    case GRN_TABLE_HASH_KEY:
      id = grn_hash_at(ctx, (grn_hash *)table, id);
      break;
    case GRN_TABLE_NO_KEY:
      id = grn_array_at(ctx, (grn_array *)table, id);
      break;
    default:
      id = GRN_ID_NIL;
    }
  }
  GRN_API_RETURN(id);
}

static inline grn_id
grn_table_add_v_inline(grn_ctx *ctx,
                       grn_obj *table,
                       const void *key,
                       int key_size,
                       void **value,
                       int *added)
{
  grn_id id = GRN_ID_NIL;
  if (!key || !key_size) {
    return GRN_ID_NIL;
  }
  if (table) {
    switch (table->header.type) {
    case GRN_TABLE_PAT_KEY:
      WITH_NORMALIZE((grn_pat *)table, key, key_size, {
        id = grn_pat_add(ctx, (grn_pat *)table, key, key_size, value, added);
      });
      break;
    case GRN_TABLE_DAT_KEY:
      WITH_NORMALIZE((grn_dat *)table, key, key_size, {
        id = grn_dat_add(ctx, (grn_dat *)table, key, key_size, value, added);
      });
      break;
    case GRN_TABLE_HASH_KEY:
      WITH_NORMALIZE((grn_hash *)table, key, key_size, {
        id = grn_hash_add(ctx, (grn_hash *)table, key, key_size, value, added);
      });
      break;
    case GRN_TABLE_NO_KEY:
      id = grn_array_add(ctx, (grn_array *)table, value);
      if (added) {
        *added = id ? 1 : 0;
      }
      break;
    }
  }
  return id;
}

grn_id
grn_table_add_v(grn_ctx *ctx,
                grn_obj *table,
                const void *key,
                int key_size,
                void **value,
                int *added)
{
  grn_id id;
  GRN_API_ENTER;
  id = grn_table_add_v_inline(ctx, table, key, key_size, value, added);
  GRN_API_RETURN(id);
}

grn_id
grn_table_get_v(
  grn_ctx *ctx, grn_obj *table, const void *key, int key_size, void **value)
{
  grn_id id = GRN_ID_NIL;
  GRN_API_ENTER;
  if (table) {
    switch (table->header.type) {
    case GRN_TABLE_PAT_KEY:
      WITH_NORMALIZE((grn_pat *)table, key, key_size, {
        id = grn_pat_get(ctx, (grn_pat *)table, key, key_size, value);
      });
      break;
    case GRN_TABLE_DAT_KEY:
      WITH_NORMALIZE((grn_dat *)table, key, key_size, {
        id = grn_dat_get(ctx, (grn_dat *)table, key, key_size, value);
      });
      break;
    case GRN_TABLE_HASH_KEY:
      WITH_NORMALIZE((grn_hash *)table, key, key_size, {
        id = grn_hash_get(ctx, (grn_hash *)table, key, key_size, value);
      });
      break;
    }
  }
  GRN_API_RETURN(id);
}

int
grn_table_get_key(
  grn_ctx *ctx, grn_obj *table, grn_id id, void *keybuf, int buf_size)
{
  int r = 0;
  GRN_API_ENTER;
  if (table) {
    if (table->header.type == GRN_DB) {
      table = ((grn_db *)table)->keys;
    }
    switch (table->header.type) {
    case GRN_TABLE_HASH_KEY:
      r = grn_hash_get_key(ctx, (grn_hash *)table, id, keybuf, buf_size);
      break;
    case GRN_TABLE_PAT_KEY:
      r = grn_pat_get_key(ctx, (grn_pat *)table, id, keybuf, buf_size);
      break;
    case GRN_TABLE_DAT_KEY:
      r = grn_dat_get_key(ctx, (grn_dat *)table, id, keybuf, buf_size);
      break;
    case GRN_TABLE_NO_KEY:
      {
        grn_array *a = (grn_array *)table;
        if (a->obj.header.domain) {
          if (buf_size >= (int)(a->value_size)) {
            r = grn_array_get_value(ctx, a, id, keybuf);
          } else {
            r = a->value_size;
          }
        }
      }
      break;
    }
  }
  GRN_API_RETURN(r);
}

int
grn_table_get_key2(grn_ctx *ctx, grn_obj *table, grn_id id, grn_obj *bulk)
{
  int r = 0;
  GRN_API_ENTER;
  if (table) {
    if (table->header.type == GRN_DB) {
      table = ((grn_db *)table)->keys;
    }
    switch (table->header.type) {
    case GRN_TABLE_HASH_KEY:
      r = grn_hash_get_key2(ctx, (grn_hash *)table, id, bulk);
      break;
    case GRN_TABLE_PAT_KEY:
      r = grn_pat_get_key2(ctx, (grn_pat *)table, id, bulk);
      break;
    case GRN_TABLE_DAT_KEY:
      r = grn_dat_get_key2(ctx, (grn_dat *)table, id, bulk);
      break;
    case GRN_TABLE_NO_KEY:
      {
        grn_array *a = (grn_array *)table;
        if (a->obj.header.domain) {
          if (!grn_bulk_space(ctx, bulk, a->value_size)) {
            char *curr = GRN_BULK_CURR(bulk);
            r = grn_array_get_value(ctx, a, id, curr - a->value_size);
          }
        }
      }
      break;
    }
  }
  GRN_API_RETURN(r);
}

static grn_rc
grn_obj_clear_value(grn_ctx *ctx, grn_obj *obj, grn_id id)
{
  grn_rc rc = GRN_SUCCESS;
  if (GRN_DB_OBJP(obj)) {
    grn_id range = DB_OBJ(obj)->range;
    switch (obj->header.type) {
    case GRN_COLUMN_VAR_SIZE:
      if (!grn_obj_is_empty(ctx, obj, id)) {
        grn_obj buf;
        GRN_VOID_INIT(&buf);
        rc = grn_obj_set_value(ctx, obj, id, &buf, GRN_OBJ_SET);
        GRN_OBJ_FIN(ctx, &buf);
      }
      break;
    case GRN_COLUMN_FIX_SIZE:
      {
        grn_obj buf;
        GRN_OBJ_INIT(&buf, GRN_BULK, 0, range);
        rc = grn_obj_set_value(ctx, obj, id, &buf, GRN_OBJ_SET);
        GRN_OBJ_FIN(ctx, &buf);
      }
      break;
    default:
      break;
    }
  }
  return rc;
}

grn_rc
grn_table_delete_data_init(grn_ctx *ctx,
                           grn_table_delete_data *data,
                           grn_obj *table)
{
  data->table = table;
  data->id = GRN_ID_NIL;
  data->key = NULL;
  data->key_size = 0;
  data->optarg = NULL;
  GRN_VOID_INIT(&(data->columns));
  GRN_VOID_INIT(&(data->index_columns));
  return GRN_SUCCESS;
}

grn_rc
grn_table_delete_data_fin(grn_ctx *ctx, grn_table_delete_data *data)
{
  grn_obj *columns = &(data->columns);
  if (columns->header.type != GRN_DB_VOID) {
    size_t n = GRN_PTR_VECTOR_SIZE(columns);
    size_t i;
    for (i = 0; i < n; i++) {
      grn_obj *column = GRN_PTR_VALUE_AT(columns, i);
      grn_obj_unref(ctx, column);
    }
  }
  GRN_OBJ_FIN(ctx, columns);

  GRN_OBJ_FIN(ctx, &(data->index_columns));

  return GRN_SUCCESS;
}

static inline grn_obj *
grn_table_delete_data_get_columns(grn_ctx *ctx, grn_table_delete_data *data)
{
  grn_obj *columns = &(data->columns);
  if (columns->header.type == GRN_DB_VOID) {
    GRN_PTR_INIT(columns, GRN_OBJ_VECTOR, GRN_ID_NIL);
    grn_hash *all_columns = grn_table_all_columns(ctx, data->table);
    if (all_columns) {
      GRN_HASH_EACH_BEGIN(ctx, all_columns, cursor, column_entry_id)
      {
        void *key;
        grn_hash_cursor_get_key(ctx, cursor, &key);
        grn_id column_id = *((grn_id *)key);
        grn_obj *column = grn_ctx_at(ctx, column_id);
        if (column) {
          GRN_PTR_PUT(ctx, columns, column);
        }
      }
      GRN_HASH_EACH_END(ctx, cursor);
    }
  }
  return columns;
}

static inline grn_obj *
grn_table_delete_data_get_index_columns(grn_ctx *ctx,
                                        grn_table_delete_data *data)
{
  grn_obj *index_columns = &(data->index_columns);
  if (index_columns->header.type == GRN_DB_VOID) {
    GRN_PTR_INIT(index_columns, GRN_OBJ_VECTOR, GRN_ID_NIL);
    grn_obj *columns = grn_table_delete_data_get_columns(ctx, data);
    size_t n = GRN_PTR_VECTOR_SIZE(columns);
    size_t i;
    for (i = 0; i < n; i++) {
      grn_obj *column = GRN_PTR_VALUE_AT(columns, i);
      if (grn_obj_is_index_column(ctx, column)) {
        GRN_PTR_PUT(ctx, index_columns, column);
      }
    }
  }
  return index_columns;
}

static void
call_delete_hook(grn_ctx *ctx, grn_table_delete_data *data)
{
  if (data->id) {
    grn_hook *hooks = DB_OBJ(data->table)->hooks[GRN_HOOK_DELETE];
    if (hooks) {
      // todo : grn_proc_ctx_open()
      grn_obj id_, flags_, oldvalue_, value_;
      grn_proc_ctx pctx;
      grn_proc_ctx_init(&pctx, hooks, 4, 4);
      GRN_UINT32_INIT(&id_, 0);
      GRN_UINT32_INIT(&flags_, 0);
      GRN_TEXT_INIT(&oldvalue_, GRN_OBJ_DO_SHALLOW_COPY);
      GRN_TEXT_INIT(&value_, 0);
      GRN_TEXT_SET_REF(&oldvalue_, data->key, data->key_size);
      GRN_UINT32_SET(ctx, &id_, data->id);
      GRN_UINT32_SET(ctx, &flags_, GRN_OBJ_SET);
      while (hooks) {
        grn_ctx_push(ctx, &id_);
        grn_ctx_push(ctx, &oldvalue_);
        grn_ctx_push(ctx, &value_);
        grn_ctx_push(ctx, &flags_);
        pctx.caller = NULL;
        pctx.currh = hooks;
        if (hooks->proc) {
          hooks->proc->funcs[PROC_INIT](ctx,
                                        1,
                                        &(data->table),
                                        &(pctx.user_data));
        } else {
          grn_obj_default_set_value_hook(ctx,
                                         1,
                                         &(data->table),
                                         &(pctx.user_data));
        }
        if (ctx->rc) {
          break;
        }
        hooks = hooks->next;
        pctx.offset++;
      }
    }
  }
}

static void
clear_column_values(grn_ctx *ctx, grn_table_delete_data *data)
{
  if (data->id == GRN_ID_NIL) {
    return;
  }

  grn_obj *columns = grn_table_delete_data_get_columns(ctx, data);
  size_t n = GRN_PTR_VECTOR_SIZE(columns);
  size_t i;
  for (i = 0; i < n; i++) {
    grn_obj *column = GRN_PTR_VALUE_AT(columns, i);
    grn_obj_clear_value(ctx, column, data->id);
  }
}

static void
delete_reference_records_in_index(grn_ctx *ctx,
                                  grn_table_delete_data *data,
                                  grn_obj *index)
{
  grn_ii *ii = (grn_ii *)index;
  grn_ii_cursor *ii_cursor = NULL;
  grn_posting *posting;
  grn_obj source_ids;
  unsigned int i, n_ids;
  grn_obj sources;
  bool have_reference_source = false;

  GRN_UINT32_INIT(&source_ids, GRN_OBJ_VECTOR);
  GRN_PTR_INIT(&sources, GRN_OBJ_VECTOR, 0);

  grn_obj_get_info(ctx, index, GRN_INFO_SOURCE, &source_ids);
  n_ids = GRN_BULK_VSIZE(&source_ids) / sizeof(grn_id);
  if (n_ids == 0) {
    goto exit;
  }

  for (i = 0; i < n_ids; i++) {
    grn_id source_id;
    grn_obj *source;

    source_id = GRN_UINT32_VALUE_AT(&source_ids, i);
    source = grn_ctx_at(ctx, source_id);
    if (grn_obj_get_range(ctx, source) == index->header.domain) {
      GRN_PTR_PUT(ctx, &sources, source);
      have_reference_source = true;
    } else {
      grn_obj_unlink(ctx, source);
      GRN_PTR_PUT(ctx, &sources, NULL);
    }
  }

  if (!have_reference_source) {
    goto exit;
  }

  ii_cursor = grn_ii_cursor_open(ctx,
                                 ii,
                                 data->id,
                                 GRN_ID_NIL,
                                 GRN_ID_MAX,
                                 ii->n_elements,
                                 0);
  if (!ii_cursor) {
    goto exit;
  }

  while ((posting = grn_ii_cursor_next(ctx, ii_cursor))) {
    grn_obj *source = GRN_PTR_VALUE_AT(&sources, posting->sid - 1);
    if (!source) {
      continue;
    }
    switch (source->header.type) {
    case GRN_COLUMN_VAR_SIZE:
      switch (source->header.flags & GRN_OBJ_COLUMN_TYPE_MASK) {
      case GRN_OBJ_COLUMN_SCALAR:
        grn_obj_clear_value(ctx, source, posting->rid);
        break;
      case GRN_OBJ_COLUMN_VECTOR:
        {
          grn_obj value;
          grn_obj new_value;
          GRN_TEXT_INIT(&value, 0);
          grn_obj_get_value(ctx, source, posting->rid, &value);
          if (value.header.type == GRN_UVECTOR) {
            GRN_RECORD_INIT(&new_value, GRN_OBJ_VECTOR, value.header.domain);
            if (grn_obj_is_weight_uvector(ctx, &value)) {
              new_value.header.flags |= GRN_OBJ_WITH_WEIGHT;
            }
            uint32_t n = grn_uvector_size(ctx, &value);
            uint32_t i;
            for (i = 0; i < n; i++) {
              float weight;
              grn_id reference_id =
                grn_uvector_get_element_record(ctx, &value, i, &weight);
              if (reference_id == data->id) {
                continue;
              }
              grn_uvector_add_element_record(ctx,
                                             &new_value,
                                             reference_id,
                                             weight);
            }
          } else {
            unsigned int i, n_elements;
            GRN_TEXT_INIT(&new_value, GRN_OBJ_VECTOR);
            n_elements = grn_vector_size(ctx, &value);
            for (i = 0; i < n_elements; i++) {
              const char *content;
              unsigned int content_length;
              uint32_t weight;
              grn_id domain;
              content_length = grn_vector_get_element(ctx,
                                                      &value,
                                                      i,
                                                      &content,
                                                      &weight,
                                                      &domain);
              if (grn_table_get(ctx, data->table, content, content_length) ==
                  data->id) {
                continue;
              }
              grn_vector_add_element(ctx,
                                     &new_value,
                                     content,
                                     content_length,
                                     weight,
                                     domain);
            }
          }
          grn_obj_set_value(ctx, source, posting->rid, &new_value, GRN_OBJ_SET);
          GRN_OBJ_FIN(ctx, &new_value);
          GRN_OBJ_FIN(ctx, &value);
        }
        break;
      }
      break;
    case GRN_COLUMN_FIX_SIZE:
      grn_obj_clear_value(ctx, source, posting->rid);
      break;
    }
  }

exit:
  if (ii_cursor) {
    grn_ii_cursor_close(ctx, ii_cursor);
  }
  grn_obj_unlink(ctx, &source_ids);
  {
    int i, n_sources;
    n_sources = GRN_BULK_VSIZE(&sources) / sizeof(grn_obj *);
    for (i = 0; i < n_sources; i++) {
      grn_obj *source = GRN_PTR_VALUE_AT(&sources, i);
      grn_obj_unlink(ctx, source);
    }
    grn_obj_unlink(ctx, &sources);
  }
}

static grn_rc
delete_reference_records(grn_ctx *ctx, grn_table_delete_data *data)
{
  grn_obj *index_columns = grn_table_delete_data_get_index_columns(ctx, data);
  size_t n = GRN_PTR_VECTOR_SIZE(index_columns);
  size_t i;
  for (i = 0; i < n; i++) {
    grn_obj *index_column = GRN_PTR_VALUE_AT(index_columns, i);
    delete_reference_records_in_index(ctx, data, index_column);
    if (ctx->rc != GRN_SUCCESS) {
      break;
    }
  }

  return ctx->rc;
}

static grn_rc
grn_table_delete_prepare(grn_ctx *ctx, grn_table_delete_data *data)
{
  grn_rc rc = delete_reference_records(ctx, data);
  if (rc != GRN_SUCCESS) {
    return rc;
  }
  call_delete_hook(ctx, data);
  clear_column_values(ctx, data);

  return rc;
}

grn_rc
grn_table_delete(grn_ctx *ctx,
                 grn_obj *table,
                 const void *key,
                 unsigned int key_size)
{
  grn_id rid = GRN_ID_NIL;
  grn_rc rc = GRN_INVALID_ARGUMENT;
  GRN_API_ENTER;
  if (table) {
    if (key && key_size) {
      rid = grn_table_get(ctx, table, key, key_size);
    }
    if (rid) {
      grn_table_delete_data data;
      grn_table_delete_data_init(ctx, &data, table);
      data.id = rid;
      switch (table->header.type) {
      case GRN_DB:
        /* todo : delete tables and columns from db */
        break;
      case GRN_TABLE_PAT_KEY:
        WITH_NORMALIZE((grn_pat *)table, key, key_size, {
          grn_pat *pat = (grn_pat *)table;
          GRN_TABLE_LOCK_BEGIN(ctx, table)
          {
            data.key = key;
            data.key_size = key_size;
            rc = grn_table_delete_prepare(ctx, &data);
            if (rc == GRN_SUCCESS) {
              rc = grn_pat_delete(ctx, pat, key, key_size, NULL);
            }
          }
          GRN_TABLE_LOCK_END(ctx);
        });
        break;
      case GRN_TABLE_DAT_KEY:
        WITH_NORMALIZE((grn_dat *)table, key, key_size, {
          grn_dat *dat = (grn_dat *)table;
          GRN_TABLE_LOCK_BEGIN(ctx, table)
          {
            data.key = key;
            data.key_size = key_size;
            rc = grn_table_delete_prepare(ctx, &data);
            if (rc == GRN_SUCCESS) {
              rc = grn_dat_delete(ctx, dat, key, key_size, NULL);
            }
          }
          GRN_TABLE_LOCK_END(ctx);
        });
        break;
      case GRN_TABLE_HASH_KEY:
        WITH_NORMALIZE((grn_hash *)table, key, key_size, {
          grn_hash *hash = (grn_hash *)table;
          GRN_TABLE_LOCK_BEGIN(ctx, table)
          {
            data.key = key;
            data.key_size = key_size;
            rc = grn_table_delete_prepare(ctx, &data);
            if (rc == GRN_SUCCESS) {
              rc = grn_hash_delete(ctx, hash, key, key_size, NULL);
            }
          }
          GRN_TABLE_LOCK_END(ctx);
        });
        break;
      }
      grn_table_delete_data_fin(ctx, &data);
      if (rc == GRN_SUCCESS) {
        grn_obj_touch(ctx, table, NULL);
      }
    }
  }
  GRN_API_RETURN(rc);
}

grn_rc
grn_table_delete_by_id_without_lock(grn_ctx *ctx, grn_table_delete_data *data)
{
  grn_rc rc = GRN_INVALID_ARGUMENT;
  grn_obj *table = data->table;
  if (table) {
    grn_id id = data->id;
    if (id != GRN_ID_NIL) {
      if (!data->key && table->header.type != GRN_TABLE_NO_KEY) {
        data->key = _grn_table_key(ctx, table, id, &(data->key_size));
      }
      rc = grn_table_delete_prepare(ctx, data);
      if (rc != GRN_SUCCESS) {
        goto exit;
      }
      grn_table_delete_optarg *optarg = data->optarg;
      // todo : support optarg
      switch (table->header.type) {
      case GRN_TABLE_PAT_KEY:
        rc = grn_pat_delete_by_id(ctx, (grn_pat *)table, id, optarg);
        break;
      case GRN_TABLE_DAT_KEY:
        rc = grn_dat_delete_by_id(ctx, (grn_dat *)table, id, optarg);
        break;
      case GRN_TABLE_HASH_KEY:
        rc = grn_hash_delete_by_id(ctx, (grn_hash *)table, id, optarg);
        break;
      case GRN_TABLE_NO_KEY:
        rc = grn_array_delete_by_id(ctx, (grn_array *)table, id, optarg);
        break;
      }
    }
  }
exit:
  return rc;
}

grn_rc
grn_table_delete_by_id(grn_ctx *ctx, grn_obj *table, grn_id id)
{
  grn_rc rc;
  GRN_API_ENTER;
  rc = ctx->rc;
  grn_table_delete_data data;
  grn_table_delete_data_init(ctx, &data, table);
  data.id = id;
  GRN_TABLE_LOCK_BEGIN(ctx, table)
  {
    rc = grn_table_delete_by_id_without_lock(ctx, &data);
  }
  GRN_TABLE_LOCK_END(ctx);
  grn_table_delete_data_fin(ctx, &data);
  if (rc == GRN_SUCCESS && ctx->rc != GRN_SUCCESS) {
    rc = ctx->rc;
  }
  if (rc == GRN_SUCCESS) {
    grn_obj_touch(ctx, table, NULL);
  }
  GRN_API_RETURN(rc);
}

grn_rc
grn_ja_truncate(grn_ctx *ctx, grn_ja *ja);
grn_rc
grn_ra_truncate(grn_ctx *ctx, grn_ra *ra);

grn_rc
grn_column_truncate(grn_ctx *ctx, grn_obj *column)
{
  grn_rc rc = GRN_INVALID_ARGUMENT;
  GRN_API_ENTER;
  if (column) {
    grn_hook *hooks;
    switch (column->header.type) {
    case GRN_COLUMN_INDEX:
      rc = grn_ii_truncate(ctx, (grn_ii *)column);
      break;
    case GRN_COLUMN_VAR_SIZE:
      for (hooks = DB_OBJ(column)->hooks[GRN_HOOK_SET]; hooks;
           hooks = hooks->next) {
        grn_obj_default_set_value_hook_data *data =
          (void *)GRN_NEXT_ADDR(hooks);
        grn_obj *target = grn_ctx_at(ctx, data->target);
        if (target->header.type != GRN_COLUMN_INDEX) {
          continue;
        }
        if ((rc = grn_ii_truncate(ctx, (grn_ii *)target))) {
          goto exit;
        }
      }
      rc = grn_ja_truncate(ctx, (grn_ja *)column);
      break;
    case GRN_COLUMN_FIX_SIZE:
      for (hooks = DB_OBJ(column)->hooks[GRN_HOOK_SET]; hooks;
           hooks = hooks->next) {
        grn_obj_default_set_value_hook_data *data =
          (void *)GRN_NEXT_ADDR(hooks);
        grn_obj *target = grn_ctx_at(ctx, data->target);
        if (target->header.type != GRN_COLUMN_INDEX) {
          continue;
        }
        if ((rc = grn_ii_truncate(ctx, (grn_ii *)target))) {
          goto exit;
        }
      }
      rc = grn_ra_truncate(ctx, (grn_ra *)column);
      break;
    }
    if (rc == GRN_SUCCESS) {
      grn_obj_touch(ctx, column, NULL);
    }
  }
exit:
  GRN_API_RETURN(rc);
}

static grn_rc
grn_table_truncate_reference_objects(grn_ctx *ctx, grn_obj *table)
{
  grn_id table_id = grn_obj_id(ctx, table);
  if (table_id & GRN_OBJ_TMP_OBJECT) {
    /* TODO: Search ctx->impl->values and ctx->imp->temporary_columns when
     * we need to implement this. */
    return ctx->rc;
  }

  bool is_close_opened_object_mode = (grn_thread_get_limit() == 1);

  grn_table_cursor *cursor = grn_table_cursor_open(ctx,
                                                   grn_ctx_db(ctx),
                                                   NULL,
                                                   0,
                                                   NULL,
                                                   0,
                                                   0,
                                                   -1,
                                                   GRN_CURSOR_BY_ID);
  if (!cursor) {
    return ctx->rc;
  }

  grn_id id;
  while ((id = grn_table_cursor_next(ctx, cursor)) != GRN_ID_NIL) {
    grn_obj *object;

    if (is_close_opened_object_mode) {
      grn_ctx_push_temporary_open_space(ctx);
    }

    object = grn_ctx_at(ctx, id);
    if (grn_obj_is_column(ctx, object)) {
      if (grn_obj_get_range(ctx, object) == table_id) {
        grn_column_truncate(ctx, object);
      }
    } else if (grn_obj_is_table_with_key(ctx, object)) {
      if (object->header.domain == table_id) {
        grn_table_truncate(ctx, object);
      }
    }
    grn_obj_unlink(ctx, object);

    if (is_close_opened_object_mode) {
      grn_ctx_pop_temporary_open_space(ctx);
    }

    if (ctx->rc != GRN_SUCCESS) {
      break;
    }
  }
  grn_table_cursor_close(ctx, cursor);

  return ctx->rc;
}

grn_rc
grn_table_truncate(grn_ctx *ctx, grn_obj *table)
{
  grn_rc rc = GRN_INVALID_ARGUMENT;
  GRN_API_ENTER;
  if (table) {
    grn_hash *cols;
    grn_obj tokenizer;
    grn_obj normalizers;
    grn_obj token_filters;
    if ((cols = grn_hash_create(ctx,
                                NULL,
                                sizeof(grn_id),
                                0,
                                GRN_OBJ_TABLE_HASH_KEY | GRN_HASH_TINY))) {
      if (grn_table_columns(ctx, table, "", 0, (grn_obj *)cols)) {
        grn_id *key;
        GRN_HASH_EACH(ctx, cols, id, &key, NULL, NULL, {
          grn_obj *col = grn_ctx_at(ctx, *key);
          if (col) {
            grn_column_truncate(ctx, col);
          }
        });
      }
      grn_hash_close(ctx, cols);
    }
    if (table->header.type != GRN_TABLE_NO_KEY) {
      GRN_TEXT_INIT(&tokenizer, 0);
      grn_table_get_default_tokenizer_string(ctx, table, &tokenizer);
      GRN_TEXT_INIT(&normalizers, 0);
      grn_table_get_normalizers_string(ctx, table, &normalizers);
      GRN_TEXT_INIT(&token_filters, 0);
      grn_table_get_token_filters_string(ctx, table, &token_filters);

      rc = grn_table_truncate_reference_objects(ctx, table);
      if (rc != GRN_SUCCESS) {
        goto exit;
      }
    }
    switch (table->header.type) {
    case GRN_TABLE_PAT_KEY:
      rc = grn_pat_truncate(ctx, (grn_pat *)table);
      break;
    case GRN_TABLE_DAT_KEY:
      rc = grn_dat_truncate(ctx, (grn_dat *)table);
      break;
    case GRN_TABLE_HASH_KEY:
      rc = grn_hash_truncate(ctx, (grn_hash *)table);
      break;
    case GRN_TABLE_NO_KEY:
      rc = grn_array_truncate(ctx, (grn_array *)table);
      break;
    }
    if (table->header.type != GRN_TABLE_NO_KEY) {
      if (GRN_TEXT_LEN(&tokenizer) > 0) {
        grn_obj_set_info(ctx, table, GRN_INFO_DEFAULT_TOKENIZER, &tokenizer);
      }
      GRN_OBJ_FIN(ctx, &tokenizer);
      if (GRN_TEXT_LEN(&normalizers) > 0) {
        grn_obj_set_info(ctx, table, GRN_INFO_NORMALIZERS, &normalizers);
      }
      GRN_OBJ_FIN(ctx, &normalizers);
      if (GRN_TEXT_LEN(&token_filters) > 0) {
        grn_obj_set_info(ctx, table, GRN_INFO_TOKEN_FILTERS, &token_filters);
      }
      GRN_OBJ_FIN(ctx, &token_filters);
    }
    if (rc == GRN_SUCCESS) {
      grn_obj_touch(ctx, table, NULL);
    }
  }
exit:
  GRN_API_RETURN(rc);
}

grn_rc
grn_table_get_info(grn_ctx *ctx,
                   grn_obj *table,
                   grn_table_flags *flags,
                   grn_encoding *encoding,
                   grn_obj **tokenizer,
                   grn_obj **normalizer,
                   grn_obj **token_filters)
{
  grn_rc rc = GRN_INVALID_ARGUMENT;
  GRN_API_ENTER;
  if (table) {
    switch (table->header.type) {
    case GRN_TABLE_PAT_KEY:
      if (flags) {
        *flags = ((grn_pat *)table)->header->flags;
      }
      if (encoding) {
        *encoding = ((grn_pat *)table)->encoding;
      }
      if (tokenizer) {
        *tokenizer = ((grn_pat *)table)->tokenizer.proc;
      }
      if (normalizer) {
        *normalizer =
          grn_table_modules_get_proc(ctx,
                                     &(((grn_pat *)table)->normalizers),
                                     0);
      }
      if (token_filters) {
        *token_filters = &(((grn_pat *)table)->token_filter_procs);
      }
      rc = GRN_SUCCESS;
      break;
    case GRN_TABLE_DAT_KEY:
      if (flags) {
        *flags = ((grn_dat *)table)->header->flags;
      }
      if (encoding) {
        *encoding = ((grn_dat *)table)->encoding;
      }
      if (tokenizer) {
        *tokenizer = ((grn_dat *)table)->tokenizer.proc;
      }
      if (normalizer) {
        *normalizer =
          grn_table_modules_get_proc(ctx,
                                     &(((grn_dat *)table)->normalizers),
                                     0);
      }
      if (token_filters) {
        *token_filters = &(((grn_dat *)table)->token_filter_procs);
      }
      rc = GRN_SUCCESS;
      break;
    case GRN_TABLE_HASH_KEY:
      if (flags) {
        *flags = ((grn_hash *)table)->header.common->flags;
      }
      if (encoding) {
        *encoding = ((grn_hash *)table)->encoding;
      }
      if (tokenizer) {
        *tokenizer = ((grn_hash *)table)->tokenizer.proc;
      }
      if (normalizer) {
        *normalizer =
          grn_table_modules_get_proc(ctx,
                                     &(((grn_hash *)table)->normalizers),
                                     0);
      }
      if (token_filters) {
        *token_filters = &(((grn_hash *)table)->token_filter_procs);
      }
      rc = GRN_SUCCESS;
      break;
    case GRN_TABLE_NO_KEY:
      if (flags) {
        *flags = grn_array_get_flags(ctx, ((grn_array *)table));
      }
      if (encoding) {
        *encoding = GRN_ENC_NONE;
      }
      if (tokenizer) {
        *tokenizer = NULL;
      }
      if (normalizer) {
        *normalizer = NULL;
      }
      if (token_filters) {
        *token_filters = NULL;
      }
      rc = GRN_SUCCESS;
      break;
    }
  }
  GRN_API_RETURN(rc);
}

unsigned int
grn_table_size(grn_ctx *ctx, grn_obj *table)
{
  unsigned int n = 0;
  GRN_API_ENTER;
  if (table) {
    switch (table->header.type) {
    case GRN_DB:
      n = grn_table_size(ctx, ((grn_db *)table)->keys);
      break;
    case GRN_TABLE_PAT_KEY:
      n = grn_pat_size(ctx, (grn_pat *)table);
      break;
    case GRN_TABLE_DAT_KEY:
      n = grn_dat_size(ctx, (grn_dat *)table);
      break;
    case GRN_TABLE_HASH_KEY:
      n = grn_hash_size(ctx, (grn_hash *)table);
      break;
    case GRN_TABLE_NO_KEY:
      n = grn_array_size(ctx, (grn_array *)table);
      break;
    default:
      ERR(GRN_INVALID_ARGUMENT,
          "[table][size] must be table or DB: <%s>(%u)",
          grn_obj_type_to_string(table->header.type),
          table->header.type);
      break;
    }
  } else {
    ERR(GRN_INVALID_ARGUMENT, "[table][size] must not NULL");
  }
  GRN_API_RETURN(n);
}

grn_table_cursor *
grn_table_cursor_open(grn_ctx *ctx,
                      grn_obj *table,
                      const void *min,
                      unsigned int min_size,
                      const void *max,
                      unsigned int max_size,
                      int offset,
                      int limit,
                      int flags)
{
  const char *tag = "[table][cursor][open]";
  grn_rc rc;
  grn_table_cursor *tc = NULL;
  unsigned int table_size;
  GRN_API_ENTER;
  if (!table) {
    ERR(GRN_INVALID_ARGUMENT, "%s table must not be NULL", tag);
    GRN_API_RETURN(NULL);
  }
  table_size = grn_table_size(ctx, table);
  if (table_size == 0 && ctx->rc != GRN_SUCCESS) {
    char message[GRN_CTX_MSGSIZE];
    grn_strcpy(message, GRN_CTX_MSGSIZE, ctx->errbuf);
    ERR(ctx->rc, "%s failed to get table size: %s", tag, message);
    GRN_API_RETURN(NULL);
  }
  if (flags & GRN_CURSOR_PREFIX) {
    if (offset < 0) {
      ERR(GRN_TOO_SMALL_OFFSET,
          "%s can't use negative offset with GRN_CURSOR_PREFIX: %d",
          tag,
          offset);
    } else if (offset != 0 && (unsigned int)offset >= table_size) {
      ERR(GRN_TOO_LARGE_OFFSET,
          "%s offset is not less than table size: offset:%d, table_size:%d",
          tag,
          offset,
          table_size);
    } else {
      if (limit < -1) {
        ERR(GRN_TOO_SMALL_LIMIT,
            "%s can't use smaller limit than -1 with GRN_CURSOR_PREFIX: %d",
            tag,
            limit);
      } else if (limit == -1) {
        limit = table_size;
      }
    }
  } else {
    rc = grn_output_range_normalize(ctx, table_size, &offset, &limit);
    if (rc != GRN_SUCCESS) {
      char name[GRN_TABLE_MAX_KEY_SIZE];
      int name_size;
      name_size = grn_obj_name(ctx, table, name, GRN_TABLE_MAX_KEY_SIZE);
      ERR(rc,
          "%s[%.*s] failed to normalize output range: "
          "table_size:%u, "
          "offset:%d, "
          "limit:%d",
          tag,
          name_size,
          name,
          table_size,
          offset,
          limit);
    }
  }
  if (!ctx->rc) {
    if (table->header.type == GRN_DB) {
      table = ((grn_db *)table)->keys;
    }
    switch (table->header.type) {
    case GRN_TABLE_PAT_KEY:
      {
        grn_pat *pat = (grn_pat *)table;
        WITH_NORMALIZE(pat, min, min_size, {
          WITH_NORMALIZE(pat, max, max_size, {
            grn_pat_cursor *pat_cursor;
            pat_cursor = grn_pat_cursor_open(ctx,
                                             pat,
                                             min,
                                             min_size,
                                             max,
                                             max_size,
                                             offset,
                                             limit,
                                             flags);
            tc = (grn_table_cursor *)pat_cursor;
          });
        });
      }
      break;
    case GRN_TABLE_DAT_KEY:
      {
        grn_dat *dat = (grn_dat *)table;
        WITH_NORMALIZE(dat, min, min_size, {
          WITH_NORMALIZE(dat, max, max_size, {
            grn_dat_cursor *dat_cursor;
            dat_cursor = grn_dat_cursor_open(ctx,
                                             dat,
                                             min,
                                             min_size,
                                             max,
                                             max_size,
                                             offset,
                                             limit,
                                             flags);
            tc = (grn_table_cursor *)dat_cursor;
          });
        });
      }
      break;
    case GRN_TABLE_HASH_KEY:
      {
        grn_hash *hash = (grn_hash *)table;
        WITH_NORMALIZE(hash, min, min_size, {
          WITH_NORMALIZE(hash, max, max_size, {
            grn_hash_cursor *hash_cursor;
            hash_cursor = grn_hash_cursor_open(ctx,
                                               hash,
                                               min,
                                               min_size,
                                               max,
                                               max_size,
                                               offset,
                                               limit,
                                               flags);
            tc = (grn_table_cursor *)hash_cursor;
          });
        });
      }
      break;
    case GRN_TABLE_NO_KEY:
      tc = (grn_table_cursor *)grn_array_cursor_open(ctx,
                                                     (grn_array *)table,
                                                     GRN_ID_NIL,
                                                     GRN_ID_NIL,
                                                     offset,
                                                     limit,
                                                     flags);
      break;
    }
  }
  if (tc) {
    grn_id id = grn_obj_register(ctx, ctx->impl->db, NULL, 0);
    DB_OBJ(tc)->header.domain = GRN_ID_NIL;
    DB_OBJ(tc)->range = GRN_ID_NIL;
    grn_db_obj_init(ctx, ctx->impl->db, id, DB_OBJ(tc));
  }
  GRN_API_RETURN(tc);
}

grn_table_cursor *
grn_table_cursor_open_by_id(
  grn_ctx *ctx, grn_obj *table, grn_id min, grn_id max, int flags)
{
  grn_table_cursor *tc = NULL;
  GRN_API_ENTER;
  if (table) {
    switch (table->header.type) {
    case GRN_TABLE_PAT_KEY:
      tc = (grn_table_cursor *)grn_pat_cursor_open(ctx,
                                                   (grn_pat *)table,
                                                   NULL,
                                                   0,
                                                   NULL,
                                                   0,
                                                   0,
                                                   -1,
                                                   flags);
      break;
    case GRN_TABLE_DAT_KEY:
      tc = (grn_table_cursor *)grn_dat_cursor_open(ctx,
                                                   (grn_dat *)table,
                                                   NULL,
                                                   0,
                                                   NULL,
                                                   0,
                                                   0,
                                                   -1,
                                                   flags);
      break;
    case GRN_TABLE_HASH_KEY:
      tc = (grn_table_cursor *)grn_hash_cursor_open(ctx,
                                                    (grn_hash *)table,
                                                    NULL,
                                                    0,
                                                    NULL,
                                                    0,
                                                    0,
                                                    -1,
                                                    flags);
      break;
    case GRN_TABLE_NO_KEY:
      tc = (grn_table_cursor *)
        grn_array_cursor_open(ctx, (grn_array *)table, min, max, 0, -1, flags);
      break;
    }
  }
  GRN_API_RETURN(tc);
}

grn_rc
grn_table_cursor_close(grn_ctx *ctx, grn_table_cursor *tc)
{
  const char *tag = "[table][cursor][close]";
  grn_rc rc = GRN_SUCCESS;
  GRN_API_ENTER;
  if (!tc) {
    rc = GRN_INVALID_ARGUMENT;
    ERR(rc, "%s invalid cursor", tag);
  } else {
    {
      if (DB_OBJ(tc)->finalizer) {
        DB_OBJ(tc)->finalizer(ctx, 1, (grn_obj **)&tc, &DB_OBJ(tc)->user_data);
      }
      if (DB_OBJ(tc)->source) {
        GRN_FREE(DB_OBJ(tc)->source);
      }
      /*
      grn_hook_entry entry;
      for (entry = 0; entry < GRN_N_HOOK_ENTRIES; entry++) {
        grn_hook_free(ctx, DB_OBJ(tc)->hooks[entry]);
      }
      */
      grn_obj_delete_by_id(ctx, DB_OBJ(tc)->db, DB_OBJ(tc)->id, GRN_FALSE);
    }
    switch (tc->header.type) {
    case GRN_CURSOR_TABLE_PAT_KEY:
      grn_pat_cursor_close(ctx, (grn_pat_cursor *)tc);
      break;
    case GRN_CURSOR_TABLE_DAT_KEY:
      grn_dat_cursor_close(ctx, (grn_dat_cursor *)tc);
      break;
    case GRN_CURSOR_TABLE_HASH_KEY:
      grn_hash_cursor_close(ctx, (grn_hash_cursor *)tc);
      break;
    case GRN_CURSOR_TABLE_NO_KEY:
      grn_array_cursor_close(ctx, (grn_array_cursor *)tc);
      break;
    default:
      rc = GRN_INVALID_ARGUMENT;
      ERR(rc, "%s invalid type %d", tag, tc->header.type);
      break;
    }
  }
  GRN_API_RETURN(rc);
}

static inline grn_id
grn_table_cursor_next_inline(grn_ctx *ctx, grn_table_cursor *tc)
{
  const char *tag = "[table][cursor][next]";
  grn_id id = GRN_ID_NIL;
  if (!tc) {
    ERR(GRN_INVALID_ARGUMENT, "%s invalid cursor", tag);
  } else {
    switch (tc->header.type) {
    case GRN_CURSOR_TABLE_PAT_KEY:
      id = grn_pat_cursor_next(ctx, (grn_pat_cursor *)tc);
      break;
    case GRN_CURSOR_TABLE_DAT_KEY:
      id = grn_dat_cursor_next(ctx, (grn_dat_cursor *)tc);
      break;
    case GRN_CURSOR_TABLE_HASH_KEY:
      id = grn_hash_cursor_next(ctx, (grn_hash_cursor *)tc);
      break;
    case GRN_CURSOR_TABLE_NO_KEY:
      id = grn_array_cursor_next(ctx, (grn_array_cursor *)tc);
      break;
    case GRN_CURSOR_COLUMN_INDEX:
      {
        grn_posting *ip = grn_index_cursor_next(ctx, (grn_obj *)tc, NULL);
        if (ip) {
          id = ip->rid;
        }
      }
      break;
    default:
      ERR(GRN_INVALID_ARGUMENT, "%s invalid type %d", tag, tc->header.type);
      break;
    }
  }
  return id;
}

grn_id
grn_table_cursor_next(grn_ctx *ctx, grn_table_cursor *tc)
{
  grn_id id;
  GRN_API_ENTER;
  id = grn_table_cursor_next_inline(ctx, tc);
  GRN_API_RETURN(id);
}

grn_rc
grn_table_cursor_foreach(grn_ctx *ctx,
                         grn_table_cursor *cursor,
                         grn_table_cursor_foreach_func func,
                         void *user_data)
{
  const char *tag = "[table][cursor][foreach]";
  grn_rc rc = GRN_SUCCESS;
  GRN_API_ENTER;
  if (!cursor) {
    rc = GRN_INVALID_ARGUMENT;
    ERR(GRN_INVALID_ARGUMENT, "%s invalid cursor", tag);
  } else {
    switch (cursor->header.type) {
    case GRN_CURSOR_TABLE_PAT_KEY:
      {
        grn_id id;
        while ((id = grn_pat_cursor_next(ctx, (grn_pat_cursor *)cursor))) {
          rc = func(ctx, cursor, id, user_data);
          if (rc != GRN_SUCCESS) {
            break;
          }
        }
      }
      break;
    case GRN_CURSOR_TABLE_DAT_KEY:
      {
        grn_id id;
        while ((id = grn_dat_cursor_next(ctx, (grn_dat_cursor *)cursor))) {
          rc = func(ctx, cursor, id, user_data);
          if (rc != GRN_SUCCESS) {
            break;
          }
        }
      }
      break;
    case GRN_CURSOR_TABLE_HASH_KEY:
      {
        grn_id id;
        while ((id = grn_hash_cursor_next(ctx, (grn_hash_cursor *)cursor))) {
          rc = func(ctx, cursor, id, user_data);
          if (rc != GRN_SUCCESS) {
            break;
          }
        }
      }
      break;
    case GRN_CURSOR_TABLE_NO_KEY:
      {
        grn_id id;
        while ((id = grn_array_cursor_next(ctx, (grn_array_cursor *)cursor))) {
          rc = func(ctx, cursor, id, user_data);
          if (rc != GRN_SUCCESS) {
            break;
          }
        }
      }
      break;
    case GRN_CURSOR_COLUMN_INDEX:
      {
        grn_posting *posting;
        while (
          (posting = grn_index_cursor_next(ctx, (grn_obj *)cursor, NULL))) {
          rc = func(ctx, cursor, posting->rid, user_data);
          if (rc != GRN_SUCCESS) {
            break;
          }
        }
      }
      break;
    default:
      rc = GRN_INVALID_ARGUMENT;
      ERR(rc, "%s invalid type %d", tag, cursor->header.type);
      break;
    }
  }
  GRN_API_RETURN(rc);
}

int
grn_table_cursor_get_key(grn_ctx *ctx, grn_table_cursor *tc, void **key)
{
  const char *tag = "[table][cursor][get-key]";
  int len = 0;
  GRN_API_ENTER;
  if (!tc) {
    ERR(GRN_INVALID_ARGUMENT, "%s invalid cursor", tag);
  } else {
    switch (tc->header.type) {
    case GRN_CURSOR_TABLE_PAT_KEY:
      len = grn_pat_cursor_get_key(ctx, (grn_pat_cursor *)tc, key);
      break;
    case GRN_CURSOR_TABLE_DAT_KEY:
      len =
        grn_dat_cursor_get_key(ctx, (grn_dat_cursor *)tc, (const void **)key);
      break;
    case GRN_CURSOR_TABLE_HASH_KEY:
      len = grn_hash_cursor_get_key(ctx, (grn_hash_cursor *)tc, key);
      break;
    default:
      ERR(GRN_INVALID_ARGUMENT, "%s invalid type %d", tag, tc->header.type);
      break;
    }
  }
  GRN_API_RETURN(len);
}

static inline int
grn_table_cursor_get_value_inline(grn_ctx *ctx,
                                  grn_table_cursor *tc,
                                  void **value)
{
  const char *tag = "[table][cursor][get-value]";
  int len = 0;
  if (!tc) {
    ERR(GRN_INVALID_ARGUMENT, "%s invalid cursor", tag);
  } else {
    switch (tc->header.type) {
    case GRN_CURSOR_TABLE_PAT_KEY:
      len = grn_pat_cursor_get_value(ctx, (grn_pat_cursor *)tc, value);
      break;
    case GRN_CURSOR_TABLE_DAT_KEY:
      *value = NULL;
      len = 0;
      break;
    case GRN_CURSOR_TABLE_HASH_KEY:
      len = grn_hash_cursor_get_value(ctx, (grn_hash_cursor *)tc, value);
      break;
    case GRN_CURSOR_TABLE_NO_KEY:
      len = grn_array_cursor_get_value(ctx, (grn_array_cursor *)tc, value);
      break;
    default:
      ERR(GRN_INVALID_ARGUMENT, "%s invalid type %d", tag, tc->header.type);
      break;
    }
  }
  return len;
}

int
grn_table_cursor_get_value(grn_ctx *ctx, grn_table_cursor *tc, void **value)
{
  int len;
  GRN_API_ENTER;
  len = grn_table_cursor_get_value_inline(ctx, tc, value);
  GRN_API_RETURN(len);
}

uint32_t
grn_table_cursor_get_key_value(grn_ctx *ctx,
                               grn_table_cursor *tc,
                               void **key,
                               uint32_t *key_size,
                               void **value)
{
  const char *tag = "[table][cursor][get-key-value]";
  uint32_t value_size = 0;
  GRN_API_ENTER;
  if (!tc) {
    ERR(GRN_INVALID_ARGUMENT, "%s invalid cursor", tag);
  } else {
    switch (tc->header.type) {
    case GRN_CURSOR_TABLE_PAT_KEY:
      value_size = grn_pat_cursor_get_key_value(ctx,
                                                (grn_pat_cursor *)tc,
                                                key,
                                                key_size,
                                                value);
      break;
    case GRN_CURSOR_TABLE_DAT_KEY:
      {
        uint32_t dat_key_size =
          grn_dat_cursor_get_key(ctx, (grn_dat_cursor *)tc, (const void **)key);
        if (key_size) {
          *key_size = dat_key_size;
        }
        if (value) {
          *value = NULL;
        }
      }
      break;
    case GRN_CURSOR_TABLE_HASH_KEY:
      value_size = grn_hash_cursor_get_key_value(ctx,
                                                 (grn_hash_cursor *)tc,
                                                 key,
                                                 key_size,
                                                 value);
      break;
    case GRN_CURSOR_TABLE_NO_KEY:
      if (key) {
        *key = NULL;
      }
      if (key_size) {
        *key_size = 0;
      }
      value_size =
        grn_array_cursor_get_value(ctx, (grn_array_cursor *)tc, value);
      break;
    default:
      ERR(GRN_INVALID_ARGUMENT, "%s invalid type %d", tag, tc->header.type);
      break;
    }
  }
  GRN_API_RETURN(value_size);
}

grn_rc
grn_table_cursor_set_value(grn_ctx *ctx,
                           grn_table_cursor *tc,
                           const void *value,
                           int flags)
{
  const char *tag = "[table][cursor][set-value]";
  grn_rc rc = GRN_INVALID_ARGUMENT;
  GRN_API_ENTER;
  if (!tc) {
    ERR(GRN_INVALID_ARGUMENT, "%s invalid cursor", tag);
  } else {
    switch (tc->header.type) {
    case GRN_CURSOR_TABLE_PAT_KEY:
      rc = grn_pat_cursor_set_value(ctx, (grn_pat_cursor *)tc, value, flags);
      break;
    case GRN_CURSOR_TABLE_DAT_KEY:
      rc = GRN_OPERATION_NOT_SUPPORTED;
      break;
    case GRN_CURSOR_TABLE_HASH_KEY:
      rc = grn_hash_cursor_set_value(ctx, (grn_hash_cursor *)tc, value, flags);
      break;
    case GRN_CURSOR_TABLE_NO_KEY:
      rc =
        grn_array_cursor_set_value(ctx, (grn_array_cursor *)tc, value, flags);
      break;
    default:
      ERR(GRN_INVALID_ARGUMENT, "%s invalid type %d", tag, tc->header.type);
      break;
    }
  }
  GRN_API_RETURN(rc);
}

grn_rc
grn_table_cursor_delete(grn_ctx *ctx, grn_table_cursor *tc)
{
  const char *tag = "[table][cursor][delete]";
  grn_rc rc = GRN_INVALID_ARGUMENT;
  GRN_API_ENTER;
  if (!tc) {
    ERR(GRN_INVALID_ARGUMENT, "%s invalid cursor", tag);
  } else {
    switch (tc->header.type) {
    case GRN_CURSOR_TABLE_PAT_KEY:
      {
        grn_pat_cursor *pc = (grn_pat_cursor *)tc;
        grn_table_delete_data data;
        grn_table_delete_data_init(ctx, &data, (grn_obj *)(pc->pat));
        data.id = pc->curr_rec;
        GRN_TABLE_LOCK_BEGIN(ctx, data.table)
        {
          data.key = _grn_pat_key(ctx, pc->pat, data.id, &(data.key_size));
          rc = grn_table_delete_prepare(ctx, &data);
          if (rc == GRN_SUCCESS) {
            rc = grn_pat_cursor_delete(ctx, pc, NULL);
          }
        }
        GRN_TABLE_LOCK_END(ctx);
        grn_table_delete_data_fin(ctx, &data);
      }
      break;
    case GRN_CURSOR_TABLE_DAT_KEY:
      rc = GRN_OPERATION_NOT_SUPPORTED;
      break;
    case GRN_CURSOR_TABLE_HASH_KEY:
      {
        grn_hash_cursor *hc = (grn_hash_cursor *)tc;
        grn_table_delete_data data;
        grn_table_delete_data_init(ctx, &data, (grn_obj *)(hc->hash));
        data.id = hc->curr_rec;
        GRN_TABLE_LOCK_BEGIN(ctx, data.table)
        {
          data.key = _grn_hash_key(ctx, hc->hash, data.id, &(data.key_size));
          rc = grn_table_delete_prepare(ctx, &data);
          if (rc == GRN_SUCCESS) {
            rc = grn_hash_cursor_delete(ctx, hc, NULL);
          }
        }
        GRN_TABLE_LOCK_END(ctx);
        grn_table_delete_data_fin(ctx, &data);
      }
      break;
    case GRN_CURSOR_TABLE_NO_KEY:
      {
        grn_array_cursor *ac = (grn_array_cursor *)tc;
        grn_table_delete_data data;
        grn_table_delete_data_init(ctx, &data, (grn_obj *)(ac->array));
        data.id = ac->curr_rec;
        GRN_TABLE_LOCK_BEGIN(ctx, data.table)
        {
          rc = grn_table_delete_prepare(ctx, &data);
          if (rc == GRN_SUCCESS) {
            rc = grn_array_cursor_delete(ctx, ac, NULL);
          }
        }
        GRN_TABLE_LOCK_END(ctx);
        grn_table_delete_data_fin(ctx, &data);
      }
      break;
    default:
      ERR(GRN_INVALID_ARGUMENT, "%s invalid type %d", tag, tc->header.type);
      break;
    }
  }
  GRN_API_RETURN(rc);
}

grn_obj *
grn_table_cursor_table(grn_ctx *ctx, grn_table_cursor *tc)
{
  const char *tag = "[table][cursor][table]";
  grn_obj *obj = NULL;
  GRN_API_ENTER;
  if (!tc) {
    ERR(GRN_INVALID_ARGUMENT, "%s invalid cursor", tag);
  } else {
    switch (tc->header.type) {
    case GRN_CURSOR_TABLE_PAT_KEY:
      obj = (grn_obj *)(((grn_pat_cursor *)tc)->pat);
      break;
    case GRN_CURSOR_TABLE_DAT_KEY:
      obj = (grn_obj *)(((grn_dat_cursor *)tc)->dat);
      break;
    case GRN_CURSOR_TABLE_HASH_KEY:
      obj = (grn_obj *)(((grn_hash_cursor *)tc)->hash);
      break;
    case GRN_CURSOR_TABLE_NO_KEY:
      obj = (grn_obj *)(((grn_array_cursor *)tc)->array);
      break;
    default:
      ERR(GRN_INVALID_ARGUMENT, "%s invalid type %d", tag, tc->header.type);
      break;
    }
  }
  GRN_API_RETURN(obj);
}

size_t
grn_table_cursor_get_max_n_records(grn_ctx *ctx, grn_table_cursor *cursor)
{
  const char *tag = "[table][cursor][get-max-n-records]";
  size_t max_n_records = 0;
  GRN_API_ENTER;
  if (!cursor) {
    ERR(GRN_INVALID_ARGUMENT, "%s invalid cursor", tag);
  } else {
    switch (cursor->header.type) {
    case GRN_CURSOR_TABLE_PAT_KEY:
      max_n_records = ((grn_pat_cursor *)cursor)->rest;
      if (max_n_records == GRN_ID_MAX) {
        max_n_records = grn_pat_size(ctx, ((grn_pat_cursor *)cursor)->pat);
      }
      break;
    case GRN_CURSOR_TABLE_DAT_KEY:
      max_n_records =
        grn_dat_cursor_get_max_n_records(ctx, (grn_dat_cursor *)cursor);
      break;
    case GRN_CURSOR_TABLE_HASH_KEY:
      max_n_records = ((grn_hash_cursor *)cursor)->rest;
      if (max_n_records == GRN_ID_MAX) {
        max_n_records = grn_hash_size(ctx, ((grn_hash_cursor *)cursor)->hash);
      }
      break;
    case GRN_CURSOR_TABLE_NO_KEY:
      max_n_records = ((grn_array_cursor *)cursor)->rest;
      if (max_n_records == GRN_ID_MAX) {
        max_n_records =
          grn_array_size(ctx, ((grn_array_cursor *)cursor)->array);
      }
      break;
    default:
      ERR(GRN_INVALID_ARGUMENT, "%s invalid type %d", tag, cursor->header.type);
      break;
    }
  }
  GRN_API_RETURN(max_n_records);
}

grn_rc
grn_table_search(grn_ctx *ctx,
                 grn_obj *table,
                 const void *key,
                 uint32_t key_size,
                 grn_operator mode,
                 grn_obj *res,
                 grn_operator op)
{
  grn_rc rc = GRN_SUCCESS;
  GRN_API_ENTER;
  switch (table->header.type) {
  case GRN_TABLE_PAT_KEY:
    {
      grn_pat *pat = (grn_pat *)table;
      WITH_NORMALIZE(pat, key, key_size, {
        switch (mode) {
        case GRN_OP_EXACT:
          {
            grn_id id = grn_pat_get(ctx, pat, key, key_size, NULL);
            if (id) {
              grn_table_add(ctx, res, &id, sizeof(grn_id), NULL);
            }
          }
          // todo : support op;
          break;
        case GRN_OP_LCP:
          {
            grn_id id = grn_pat_lcp_search(ctx, pat, key, key_size);
            if (id) {
              grn_table_add(ctx, res, &id, sizeof(grn_id), NULL);
            }
          }
          // todo : support op;
          break;
        case GRN_OP_SUFFIX:
          rc = grn_pat_suffix_search(ctx, pat, key, key_size, (grn_hash *)res);
          // todo : support op;
          break;
        case GRN_OP_PREFIX:
          rc = grn_pat_prefix_search(ctx, pat, key, key_size, (grn_hash *)res);
          // todo : support op;
          break;
        case GRN_OP_TERM_EXTRACT:
          {
            int len;
            grn_id tid;
            const char *sp = key;
            const char *se = sp + key_size;
            for (; sp < se; sp += len) {
              if ((tid = grn_pat_lcp_search(ctx, pat, sp, se - sp))) {
                grn_table_add(ctx, res, &tid, sizeof(grn_id), NULL);
                /* todo : nsubrec++ if GRN_OBJ_TABLE_SUBSET assigned */
              }
              if (!(len = grn_charlen(ctx, sp, se))) {
                break;
              }
            }
          }
          // todo : support op;
          break;
        default:
          rc = GRN_INVALID_ARGUMENT;
          ERR(rc,
              "[table][search][pat] invalid mode: %s",
              grn_operator_to_string(mode));
          break;
        }
      });
    }
    break;
  case GRN_TABLE_DAT_KEY:
    {
      grn_dat *dat = (grn_dat *)table;
      WITH_NORMALIZE(dat, key, key_size, {
        switch (mode) {
        case GRN_OP_EXACT:
          {
            grn_id id = grn_dat_get(ctx, dat, key, key_size, NULL);
            if (id) {
              grn_table_add(ctx, res, &id, sizeof(grn_id), NULL);
            }
          }
          break;
        case GRN_OP_PREFIX:
          {
            grn_dat_cursor *dc = grn_dat_cursor_open(ctx,
                                                     dat,
                                                     key,
                                                     key_size,
                                                     NULL,
                                                     0,
                                                     0,
                                                     -1,
                                                     GRN_CURSOR_PREFIX);
            if (dc) {
              grn_id id;
              while ((id = grn_dat_cursor_next(ctx, dc))) {
                grn_table_add(ctx, res, &id, sizeof(grn_id), NULL);
              }
              grn_dat_cursor_close(ctx, dc);
            }
          }
          break;
        case GRN_OP_LCP:
          {
            grn_id id = grn_dat_lcp_search(ctx, dat, key, key_size);
            if (id) {
              grn_table_add(ctx, res, &id, sizeof(grn_id), NULL);
            }
          }
          break;
        case GRN_OP_TERM_EXTRACT:
          {
            int len;
            grn_id tid;
            const char *sp = key;
            const char *se = sp + key_size;
            for (; sp < se; sp += len) {
              if ((tid = grn_dat_lcp_search(ctx, dat, sp, se - sp))) {
                grn_table_add(ctx, res, &tid, sizeof(grn_id), NULL);
                /* todo : nsubrec++ if GRN_OBJ_TABLE_SUBSET assigned */
              }
              if (!(len = grn_charlen(ctx, sp, se))) {
                break;
              }
            }
          }
          // todo : support op;
          break;
        default:
          rc = GRN_INVALID_ARGUMENT;
          ERR(rc,
              "[table][search][dat] invalid mode: %s",
              grn_operator_to_string(mode));
          break;
        }
      });
    }
    break;
  case GRN_TABLE_HASH_KEY:
    {
      grn_hash *hash = (grn_hash *)table;
      WITH_NORMALIZE(hash, key, key_size, {
        switch (mode) {
        case GRN_OP_EXACT:
          {
            grn_id id = grn_hash_get(ctx, hash, key, key_size, NULL);
            if (id) {
              grn_table_add(ctx, res, &id, sizeof(grn_id), NULL);
            }
          }
          break;
        default:
          rc = GRN_INVALID_ARGUMENT;
          ERR(rc,
              "[table][search][hash] invalid mode: %s",
              grn_operator_to_string(mode));
          break;
        }
      });
    }
    break;
  default:
    rc = GRN_INVALID_ARGUMENT;
    {
      grn_obj inspected;
      GRN_TEXT_INIT(&inspected, 0);
      grn_inspect_type(ctx, &inspected, table->header.type);
      ERR(rc,
          "[table][search] invalid type: %.*s",
          (int)GRN_TEXT_LEN(&inspected),
          GRN_TEXT_VALUE(&inspected));
      GRN_OBJ_FIN(ctx, &inspected);
    }
    break;
  }
  GRN_API_RETURN(rc);
}

grn_rc
grn_table_fuzzy_search(grn_ctx *ctx,
                       grn_obj *table,
                       const void *key,
                       uint32_t key_size,
                       grn_fuzzy_search_optarg *args,
                       grn_obj *res,
                       grn_operator op)
{
  grn_rc rc = GRN_SUCCESS;
  GRN_API_ENTER;
  switch (table->header.type) {
  case GRN_TABLE_PAT_KEY:
    {
      grn_pat *pat = (grn_pat *)table;
      if (!grn_table_size(ctx, res) && op == GRN_OP_OR) {
        WITH_NORMALIZE(pat, key, key_size, {
          rc = grn_pat_fuzzy_search(ctx,
                                    pat,
                                    key,
                                    key_size,
                                    args,
                                    (grn_hash *)res);
        });
      } else {
        grn_obj *hash;
        hash = grn_table_create(ctx,
                                NULL,
                                0,
                                NULL,
                                GRN_OBJ_TABLE_HASH_KEY | GRN_OBJ_WITH_SUBREC,
                                table,
                                NULL);
        WITH_NORMALIZE(pat, key, key_size, {
          rc = grn_pat_fuzzy_search(ctx,
                                    pat,
                                    key,
                                    key_size,
                                    args,
                                    (grn_hash *)hash);
        });
        if (rc == GRN_SUCCESS) {
          rc = grn_table_setoperation(ctx, res, hash, res, op);
        }
        grn_obj_unlink(ctx, hash);
      }
    }
    break;
  default:
    rc = GRN_OPERATION_NOT_SUPPORTED;
    break;
  }
  GRN_API_RETURN(rc);
}

grn_id
grn_table_next(grn_ctx *ctx, grn_obj *table, grn_id id)
{
  grn_id r = GRN_ID_NIL;
  GRN_API_ENTER;
  if (table) {
    switch (table->header.type) {
    case GRN_TABLE_PAT_KEY:
      r = grn_pat_next(ctx, (grn_pat *)table, id);
      break;
    case GRN_TABLE_DAT_KEY:
      r = grn_dat_next(ctx, (grn_dat *)table, id);
      break;
    case GRN_TABLE_HASH_KEY:
      r = grn_hash_next(ctx, (grn_hash *)table, id);
      break;
    case GRN_TABLE_NO_KEY:
      r = grn_array_next(ctx, (grn_array *)table, id);
      break;
    }
  }
  GRN_API_RETURN(r);
}

static inline void
grn_obj_search_index_report(grn_ctx *ctx, const char *tag, grn_obj *index)
{
  grn_report_index(ctx, "[object][search]", tag, index);
}

static inline void
grn_obj_search_accessor_report(grn_ctx *ctx, const char *tag, grn_obj *accessor)
{
  grn_report_accessor(ctx, "[object][search]", tag, accessor);
}

static inline grn_rc
grn_obj_search_table_id(grn_ctx *ctx,
                        grn_obj *table,
                        grn_obj *query,
                        grn_obj *res,
                        grn_operator op,
                        grn_search_optarg *optarg)
{
  grn_id id = GRN_ID_NIL;
  if (query->header.domain == DB_OBJ(table)->id) {
    id = GRN_RECORD_VALUE(query);
  } else if (query->header.domain == GRN_DB_UINT32) {
    id = GRN_UINT32_VALUE(query);
  } else {
    grn_obj id_value;
    GRN_UINT32_INIT(&id_value, 0);
    grn_rc rc = grn_obj_cast(ctx, query, &id_value, false);
    if (rc == GRN_SUCCESS) {
      id = GRN_UINT32_VALUE(&id_value);
    }
    GRN_OBJ_FIN(ctx, &id_value);
    if (rc != GRN_SUCCESS) {
      return rc;
    }
  }
  if (id != GRN_ID_NIL) {
    if (grn_table_at(ctx, table, id) == id) {
      grn_posting_internal posting = {0};
      posting.sid = 1;
      posting.weight_float = 1.0;
      posting.rid = id;
      grn_ii_posting_add_float(ctx,
                               (grn_posting *)(&posting),
                               (grn_hash *)res,
                               op);
    }
  }
  grn_ii_resolve_sel_and(ctx, (grn_hash *)res, op);
  return GRN_SUCCESS;
}

typedef struct {
  grn_obj *accessor;
  grn_obj *query;
  grn_search_optarg *optarg;
} grn_obj_search_accessor_execute_data;

static grn_rc
grn_obj_search_accessor_execute(grn_ctx *ctx,
                                grn_obj *index,
                                grn_operator mode,
                                grn_obj *res,
                                grn_operator op,
                                void *user_data)
{
  grn_obj_search_accessor_execute_data *data = user_data;
  if (grn_obj_is_accessor(ctx, index)) {
    grn_accessor *last_accessor = (grn_accessor *)index;
    switch (last_accessor->action) {
    case GRN_ACCESSOR_GET_ID:
      if (mode != GRN_OP_EQUAL) {
        return GRN_SUCCESS;
      }
      if (!grn_obj_is_table(ctx, last_accessor->obj)) {
        return GRN_SUCCESS;
      }
      grn_obj_search_accessor_report(ctx, "[id]", data->accessor);
      return grn_obj_search_table_id(ctx,
                                     last_accessor->obj,
                                     data->query,
                                     res,
                                     op,
                                     data->optarg);
    default:
      return grn_obj_search(ctx,
                            last_accessor->obj,
                            data->query,
                            res,
                            op,
                            data->optarg);
    }
  } else {
    return grn_obj_search(ctx, index, data->query, res, op, data->optarg);
  }
}

static grn_rc
grn_obj_search_column_index_by_id(grn_ctx *ctx,
                                  grn_obj *obj,
                                  grn_id tid,
                                  grn_obj *res,
                                  grn_operator op,
                                  grn_search_optarg *optarg)
{
  grn_obj_search_index_report(ctx, "[id]", obj);
  grn_ii_at(ctx, (grn_ii *)obj, tid, (grn_hash *)res, op);
  if (ctx->rc == GRN_SUCCESS) {
    grn_ii_resolve_sel_and(ctx, (grn_hash *)res, op);
  }
  return ctx->rc;
}

static grn_rc
grn_obj_search_column_index_by_key(grn_ctx *ctx,
                                   grn_obj *obj,
                                   grn_obj *query,
                                   grn_obj *res,
                                   grn_operator op,
                                   grn_search_optarg *optarg)
{
  grn_rc rc;
  grn_id key_type = GRN_ID_NIL;
  const char *key;
  unsigned int key_len;
  grn_obj casted_query;
  bool need_cast = false;
  grn_id *query_domain_keep = optarg ? optarg->query_domain : NULL;

  {
    if (grn_obj_is_index_column(ctx, obj)) {
      grn_obj *lexicon = grn_ctx_at(ctx, obj->header.domain);
      if (lexicon) {
        if (grn_table_have_tokenizer(ctx, lexicon)) {
          grn_obj source_ids;
          GRN_UINT32_INIT(&source_ids, GRN_OBJ_VECTOR);
          grn_obj_get_info(ctx, obj, GRN_INFO_SOURCE, &source_ids);
          size_t n_source_ids = GRN_UINT32_VECTOR_SIZE(&source_ids);
          if (n_source_ids >= 1) {
            grn_id source_id = GRN_UINT32_VALUE_AT(&source_ids, 0);
            grn_obj *source = grn_ctx_at(ctx, source_id);
            if (source) {
              if (grn_obj_is_table_with_key(ctx, source)) {
                key_type = source->header.domain;
              } else if (grn_obj_is_reference_column(ctx, source)) {
                const grn_id range_id = DB_OBJ(source)->range;
                grn_obj *referenced_table = grn_ctx_at(ctx, range_id);
                key_type = referenced_table->header.domain;
                grn_obj_unref(ctx, referenced_table);
              } else {
                key_type = DB_OBJ(source)->range;
              }
              need_cast =
                !grn_type_id_is_compatible(ctx, query->header.domain, key_type);
              grn_obj_unref(ctx, source);
            }
          }
          GRN_OBJ_FIN(ctx, &source_ids);
        } else {
          key_type = lexicon->header.domain;
          need_cast = (query->header.domain != key_type);
        }
        grn_obj_unref(ctx, lexicon);
      }
    } else {
      grn_obj *table = grn_ctx_at(ctx, obj->header.domain);
      if (table) {
        key_type = table->header.domain;
        need_cast =
          !grn_type_id_is_compatible(ctx, query->header.domain, key_type);
        grn_obj_unref(ctx, table);
      }
    }
  }
  if (need_cast) {
    GRN_OBJ_INIT(&casted_query, GRN_BULK, 0, key_type);
    rc = grn_obj_cast(ctx, query, &casted_query, GRN_FALSE);
    if (rc == GRN_SUCCESS) {
      key = GRN_BULK_HEAD(&casted_query);
      key_len = GRN_BULK_VSIZE(&casted_query);
      if (optarg) {
        optarg->query_domain = &key_type;
      }
    }
  } else {
    rc = GRN_SUCCESS;
    key = GRN_BULK_HEAD(query);
    key_len = GRN_BULK_VSIZE(query);
    if (optarg) {
      optarg->query_domain = &(query->header.domain);
    }
  }
  if (rc == GRN_SUCCESS) {
    if (grn_logger_pass(ctx, GRN_REPORT_INDEX_LOG_LEVEL)) {
      const char *tag;
      if (optarg) {
        switch (optarg->mode) {
        case GRN_OP_EQUAL:
          tag = "[key][equal]";
          break;
        case GRN_OP_MATCH:
          tag = "[key][match]";
          break;
        case GRN_OP_EXACT:
          tag = "[key][exact]";
          break;
        case GRN_OP_NEAR:
          tag = "[key][near]";
          break;
        case GRN_OP_NEAR_NO_OFFSET:
          tag = "[key][near-no-offset]";
          break;
        case GRN_OP_NEAR_PHRASE:
          tag = "[key][near-phrase]";
          break;
        case GRN_OP_ORDERED_NEAR_PHRASE:
          tag = "[key][ordered-near-phrase]";
          break;
        case GRN_OP_NEAR_PHRASE_PRODUCT:
          tag = "[key][near-phrase-product]";
          break;
        case GRN_OP_ORDERED_NEAR_PHRASE_PRODUCT:
          tag = "[key][ordered-near-phrase-product]";
          break;
        case GRN_OP_SIMILAR:
          tag = "[key][similar]";
          break;
        case GRN_OP_REGEXP:
          tag = "[key][regexp]";
          break;
        case GRN_OP_FUZZY:
          tag = "[key][fuzzy]";
          break;
        case GRN_OP_QUORUM:
          tag = "[key][quorum]";
          break;
        default:
          tag = "[key][unknown]";
          break;
        }
      } else {
        tag = "[key][exact]";
      }
      grn_obj_search_index_report(ctx, tag, obj);
    }
    if (optarg && optarg->mode == GRN_OP_EQUAL) {
      grn_obj *lexicon = grn_ctx_at(ctx, obj->header.domain);
      if (!lexicon) {
        rc = GRN_INVALID_ARGUMENT;
        goto exit;
      }
      grn_id token_id = grn_table_get(ctx, lexicon, key, key_len);
      if (token_id != GRN_ID_NIL) {
        grn_ii_at(ctx, (grn_ii *)obj, token_id, (grn_hash *)res, op);
      }
      grn_ii_resolve_sel_and(ctx, (grn_hash *)res, op);
    } else {
      rc = grn_ii_sel(ctx,
                      (grn_ii *)obj,
                      key,
                      key_len,
                      (grn_hash *)res,
                      op,
                      optarg);
    }
  }

exit:
  if (need_cast) {
    GRN_OBJ_FIN(ctx, &casted_query);
  }

  if (optarg) {
    optarg->query_domain = query_domain_keep;
  }

  return rc;
}

static grn_rc
grn_obj_search_column_index(grn_ctx *ctx,
                            grn_obj *obj,
                            grn_obj *query,
                            grn_obj *res,
                            grn_operator op,
                            grn_search_optarg *optarg)
{
  grn_rc rc = GRN_INVALID_ARGUMENT;

  if (DB_OBJ(obj)->range == res->header.domain) {
    switch (query->header.type) {
    case GRN_BULK:
      if (query->header.domain == obj->header.domain &&
          GRN_BULK_VSIZE(query) == sizeof(grn_id)) {
        grn_id tid = GRN_RECORD_VALUE(query);
        rc = grn_obj_search_column_index_by_id(ctx, obj, tid, res, op, optarg);
      } else {
        rc =
          grn_obj_search_column_index_by_key(ctx, obj, query, res, op, optarg);
      }
      break;
    case GRN_QUERY:
      rc = GRN_FUNCTION_NOT_IMPLEMENTED;
      break;
    }
  }

  return rc;
}

static grn_rc
grn_obj_search_column_data(grn_ctx *ctx,
                           grn_obj *obj,
                           grn_obj *query,
                           grn_obj *res,
                           grn_operator op,
                           grn_search_optarg *optarg)
{
  grn_obj *table = grn_ctx_at(ctx, obj->header.domain);
  grn_obj *expr = NULL;
  grn_obj *variable;
  GRN_EXPR_CREATE_FOR_QUERY(ctx, table, expr, variable);
  if (!expr) {
    goto exit;
  }
  grn_expr_append_obj(ctx, expr, obj, GRN_OP_GET_VALUE, 1);
  grn_expr_append_const(ctx, expr, query, GRN_OP_PUSH, 1);
  {
    grn_operator search_op = GRN_OP_MATCH;
    if (optarg && optarg->mode != GRN_OP_EXACT) {
      search_op = optarg->mode;
    }
    grn_expr_append_op(ctx, expr, search_op, 2);
  }

  grn_table_selector table_selector;
  grn_table_selector_init(ctx, &table_selector, table, expr, op);
  grn_table_selector_select(ctx, &table_selector, res);
  grn_table_selector_fin(ctx, &table_selector);

exit:
  if (expr) {
    grn_obj_close(ctx, expr);
  }

  return ctx->rc;
}

grn_rc
grn_obj_search(grn_ctx *ctx,
               grn_obj *obj,
               grn_obj *query,
               grn_obj *res,
               grn_operator op,
               grn_search_optarg *optarg)
{
  grn_rc rc = GRN_INVALID_ARGUMENT;
  GRN_API_ENTER;
  if (GRN_ACCESSORP(obj)) {
    grn_operator mode = GRN_OP_MATCH;
    if (optarg && optarg->mode != GRN_OP_EXACT) {
      mode = optarg->mode;
    }
    grn_obj_search_accessor_execute_data data;
    data.accessor = obj;
    data.query = query;
    data.optarg = optarg;
    rc = grn_accessor_execute(ctx,
                              obj,
                              grn_obj_search_accessor_execute,
                              &data,
                              mode,
                              res,
                              op);
  } else if (GRN_DB_OBJP(obj)) {
    switch (obj->header.type) {
    case GRN_TABLE_PAT_KEY:
    case GRN_TABLE_DAT_KEY:
    case GRN_TABLE_HASH_KEY:
      {
        const void *key = GRN_BULK_HEAD(query);
        uint32_t key_size = GRN_BULK_VSIZE(query);
        bool need_cast = false;
        grn_obj casted_query;
        if (!grn_type_id_is_compatible(ctx,
                                       obj->header.domain,
                                       query->header.domain)) {
          need_cast = true;
          GRN_VALUE_FIX_SIZE_INIT(&casted_query, 0, obj->header.domain);
          if (grn_obj_cast(ctx, query, &casted_query, false) == GRN_SUCCESS) {
            key = GRN_BULK_HEAD(&casted_query);
            key_size = GRN_BULK_VSIZE(&casted_query);
          }
        }
        grn_operator mode = optarg ? optarg->mode : GRN_OP_EXACT;
        if (key && key_size) {
          if (grn_logger_pass(ctx, GRN_REPORT_INDEX_LOG_LEVEL)) {
            const char *tag;
            switch (mode) {
            case GRN_OP_EQUAL:
              tag = "[table][equal]";
              break;
            case GRN_OP_EXACT:
              tag = "[table][exact]";
              break;
            case GRN_OP_LCP:
              tag = "[table][lcp]";
              break;
            case GRN_OP_SUFFIX:
              tag = "[table][suffix]";
              break;
            case GRN_OP_PREFIX:
              tag = "[table][prefix]";
              break;
            case GRN_OP_TERM_EXTRACT:
              tag = "[table][term-extract]";
              break;
            case GRN_OP_FUZZY:
              tag = "[table][fuzzy]";
              break;
            default:
              tag = "[table][unknown]";
              break;
            }
            grn_obj_search_index_report(ctx, tag, obj);
          }
          switch (mode) {
          case GRN_OP_EQUAL:
            {
              grn_posting_internal posting = {0};
              posting.rid = grn_table_get(ctx, obj, key, key_size);
              posting.weight_float = 1.0;
              if (posting.rid == GRN_ID_NIL) {
                rc = GRN_SUCCESS;
              } else {
                rc = grn_ii_posting_add_float(ctx,
                                              (grn_posting *)(&posting),
                                              (grn_hash *)res,
                                              op);
              }
              if (rc == GRN_SUCCESS) {
                grn_ii_resolve_sel_and(ctx, (grn_hash *)res, op);
              }
            }
            break;
          case GRN_OP_FUZZY:
            rc = grn_table_fuzzy_search(ctx,
                                        obj,
                                        key,
                                        key_size,
                                        &(optarg->fuzzy),
                                        res,
                                        op);
            break;
          default:
            rc = grn_table_search(ctx, obj, key, key_size, mode, res, op);
            break;
          }
        }
        if (need_cast) {
          GRN_OBJ_FIN(ctx, &casted_query);
        }
      }
      break;
    case GRN_COLUMN_INDEX:
      rc = grn_obj_search_column_index(ctx, obj, query, res, op, optarg);
      break;
    case GRN_COLUMN_FIX_SIZE:
    case GRN_COLUMN_VAR_SIZE:
      rc = grn_obj_search_column_data(ctx, obj, query, res, op, optarg);
      break;
    }
  }
  GRN_API_RETURN(rc);
}

typedef struct {
  grn_operator op;
  float weight_factor;
  grn_obj *table_dest;
  grn_obj *table_src;
  bool have_subrec;
  uint32_t value_size;
  grn_obj merge_target_vector_columns;
  grn_obj merge_target_number_columns;
} grn_table_setoperation_data;

static inline void
grn_table_setoperation_data_init_value_size(grn_ctx *ctx,
                                            grn_table_setoperation_data *data)
{
  grn_obj *table_dest = data->table_dest;
  grn_obj *table_src = data->table_src;
  data->value_size = 0;
  switch (table_dest->header.type) {
  case GRN_TABLE_HASH_KEY:
    data->value_size = ((grn_hash *)table_dest)->value_size;
    break;
  case GRN_TABLE_PAT_KEY:
    data->value_size = ((grn_pat *)table_dest)->value_size;
    break;
  case GRN_TABLE_DAT_KEY:
    data->value_size = 0;
    break;
  case GRN_TABLE_NO_KEY:
    data->value_size = ((grn_array *)table_dest)->value_size;
    break;
  }
  switch (table_src->header.type) {
  case GRN_TABLE_HASH_KEY:
    if (data->value_size < ((grn_hash *)table_src)->value_size) {
      data->value_size = ((grn_hash *)table_src)->value_size;
    }
    break;
  case GRN_TABLE_PAT_KEY:
    if (data->value_size < ((grn_pat *)table_src)->value_size) {
      data->value_size = ((grn_pat *)table_src)->value_size;
    }
    break;
  case GRN_TABLE_DAT_KEY:
    data->value_size = 0;
    break;
  case GRN_TABLE_NO_KEY:
    if (data->value_size < ((grn_array *)table_src)->value_size) {
      data->value_size = ((grn_array *)table_src)->value_size;
    }
    break;
  default:
    break;
  }
}

static inline void
grn_table_setoperation_data_init_merge_target_columns(
  grn_ctx *ctx, grn_table_setoperation_data *data)
{
  grn_obj *merge_target_vector_columns = &(data->merge_target_vector_columns);
  grn_obj *merge_target_number_columns = &(data->merge_target_number_columns);
  GRN_PTR_INIT(merge_target_vector_columns, GRN_OBJ_VECTOR, GRN_ID_NIL);
  GRN_PTR_INIT(merge_target_number_columns, GRN_OBJ_VECTOR, GRN_ID_NIL);

  grn_hash *columns_src = grn_table_all_columns(ctx, data->table_src);
  if (!columns_src) {
    return;
  }
  if (grn_hash_size(ctx, columns_src) == 0) {
    return;
  }

  GRN_HASH_EACH_BEGIN(ctx, columns_src, cursor, column_entry_id)
  {
    void *key;
    grn_hash_cursor_get_key(ctx, cursor, &key);
    grn_id column_src_id = *((grn_id *)key);
    grn_obj *column_src = grn_ctx_at(ctx, column_src_id);
    bool is_vector_src = grn_obj_is_vector_column(ctx, column_src);
    if (!(is_vector_src ||
          grn_type_id_is_number_family(ctx, DB_OBJ(column_src)->range))) {
      grn_obj_unref(ctx, column_src);
      continue;
    }
    char name[GRN_TABLE_MAX_KEY_SIZE];
    int name_size =
      grn_column_name(ctx, column_src, name, GRN_TABLE_MAX_KEY_SIZE);
    grn_obj *column_dest =
      grn_table_column(ctx, data->table_dest, name, name_size);
    if (!column_dest) {
      grn_obj_unref(ctx, column_src);
      continue;
    }
    bool is_target = false;
    if (is_vector_src) {
      if (grn_obj_is_vector_column(ctx, column_dest)) {
        GRN_PTR_PUT(ctx, merge_target_vector_columns, column_dest);
        GRN_PTR_PUT(ctx, merge_target_vector_columns, column_src);
        is_target = true;
      }
    } else {
      if (DB_OBJ(column_src)->range == DB_OBJ(column_dest)->range) {
        GRN_PTR_PUT(ctx, merge_target_number_columns, column_dest);
        GRN_PTR_PUT(ctx, merge_target_number_columns, column_src);
        is_target = true;
      }
    }
    if (!is_target) {
      grn_obj_unref(ctx, column_dest);
      grn_obj_unref(ctx, column_src);
    }
  }
  GRN_HASH_EACH_END(ctx, cursor);
}

static inline void
grn_table_setoperation_data_init(grn_ctx *ctx,
                                 grn_table_setoperation_data *data)
{
  grn_table_setoperation_data_init_value_size(ctx, data);
  grn_table_setoperation_data_init_merge_target_columns(ctx, data);
}

static inline void
grn_table_setoperation_fin_merge_target_columns(grn_ctx *ctx,
                                                grn_obj *merge_target_columns)
{
  size_t n_elements = GRN_PTR_VECTOR_SIZE(merge_target_columns);
  size_t i;
  for (i = 0; i < n_elements; i++) {
    grn_obj *column = GRN_PTR_VALUE_AT(merge_target_columns, i);
    grn_obj_unref(ctx, column);
  }
  GRN_OBJ_FIN(ctx, merge_target_columns);
}

static inline void
grn_table_setoperation_data_fin(grn_ctx *ctx, grn_table_setoperation_data *data)
{
  grn_table_setoperation_fin_merge_target_columns(
    ctx,
    &(data->merge_target_vector_columns));
  grn_table_setoperation_fin_merge_target_columns(
    ctx,
    &(data->merge_target_number_columns));
}

static inline bool
grn_table_setoperation_need_merge_columns(grn_ctx *ctx,
                                          grn_table_setoperation_data *data)
{
  return (GRN_PTR_VECTOR_SIZE(&(data->merge_target_vector_columns)) > 0) ||
         (GRN_PTR_VECTOR_SIZE(&(data->merge_target_number_columns)) > 0);
}

static inline void
grn_table_setoperation_merge_columns(grn_ctx *ctx,
                                     grn_table_setoperation_data *data,
                                     grn_id id_dest,
                                     grn_id id_src)
{
  {
    grn_obj *merge_target_columns = &(data->merge_target_vector_columns);
    size_t n_elements = GRN_PTR_VECTOR_SIZE(merge_target_columns);
    if (n_elements > 0) {
      size_t i;
      grn_obj buffer;
      GRN_VOID_INIT(&buffer);
      for (i = 0; i < n_elements; i += 2) {
        grn_obj *column_dest = GRN_PTR_VALUE_AT(merge_target_columns, i);
        grn_obj *column_src = GRN_PTR_VALUE_AT(merge_target_columns, i + 1);
        GRN_BULK_REWIND(&buffer);
        grn_obj_get_value(ctx, column_src, id_src, &buffer);
        if (grn_vector_size(ctx, &buffer) > 0) {
          grn_obj_set_value(ctx, column_dest, id_dest, &buffer, GRN_OBJ_APPEND);
        }
      }
      GRN_OBJ_FIN(ctx, &buffer);
    }
  }

  {
    grn_obj *merge_target_columns = &(data->merge_target_number_columns);
    size_t n_elements = GRN_PTR_VECTOR_SIZE(merge_target_columns);
    if (n_elements > 0) {
      size_t i;
      uint64_t zero = 0;
      grn_obj buffer;
      GRN_VOID_INIT(&buffer);
      for (i = 0; i < n_elements; i += 2) {
        grn_obj *column_dest = GRN_PTR_VALUE_AT(merge_target_columns, i);
        grn_obj *column_src = GRN_PTR_VALUE_AT(merge_target_columns, i + 1);
        GRN_BULK_REWIND(&buffer);
        grn_obj_get_value(ctx, column_src, id_src, &buffer);
        if (memcmp(GRN_BULK_HEAD(&buffer), &zero, GRN_BULK_VSIZE(&buffer)) !=
            0) {
          grn_obj_set_value(ctx, column_dest, id_dest, &buffer, GRN_OBJ_INCR);
        }
      }
      GRN_OBJ_FIN(ctx, &buffer);
    }
  }
}

static inline void
grn_table_setoperation_or(grn_ctx *ctx, grn_table_setoperation_data *data)
{
  if (data->have_subrec) {
    GRN_TABLE_EACH_BEGIN(ctx, data->table_src, cursor, id_src)
    {
      void *key_src;
      uint32_t key_src_size;
      void *value_src;
      grn_table_cursor_get_key_value(ctx,
                                     cursor,
                                     &key_src,
                                     &key_src_size,
                                     &value_src);
      void *value_dest;
      int added;
      grn_id id_dest = grn_table_add_v_inline(ctx,
                                              data->table_dest,
                                              key_src,
                                              key_src_size,
                                              &value_dest,
                                              &added);
      if (id_dest == GRN_ID_NIL) {
        if (ctx->rc == GRN_SUCCESS) {
          continue;
        } else {
          break;
        }
      }
      if (added) {
        grn_memcpy(value_dest, value_src, data->value_size);
        grn_rset_recinfo *ri_dest = value_dest;
        ri_dest->score *= data->weight_factor;
      } else {
        grn_rset_recinfo *ri_dest = value_dest;
        grn_rset_recinfo *ri_src = value_src;
        grn_table_add_subrec(ctx,
                             data->table_dest,
                             ri_dest,
                             ri_src->score * data->weight_factor,
                             NULL,
                             0);
      }
      grn_table_setoperation_merge_columns(ctx, data, id_dest, id_src);
    }
    GRN_TABLE_EACH_END(ctx, cursor);
  } else {
    GRN_TABLE_EACH_BEGIN(ctx, data->table_src, cursor, id_src)
    {
      void *key_src;
      uint32_t key_src_size = grn_table_cursor_get_key(ctx, cursor, &key_src);
      void *value_dest;
      grn_id id_dest = grn_table_add_v_inline(ctx,
                                              data->table_dest,
                                              key_src,
                                              key_src_size,
                                              &value_dest,
                                              NULL);
      if (id_dest == GRN_ID_NIL) {
        if (ctx->rc == GRN_SUCCESS) {
          continue;
        } else {
          break;
        }
      }
      grn_table_setoperation_merge_columns(ctx, data, id_dest, id_src);
    }
    GRN_TABLE_EACH_END(ctx, cursor);
  }
}

static inline void
grn_table_setoperation_and(grn_ctx *ctx, grn_table_setoperation_data *data)
{
  grn_table_delete_data delete_data;
  grn_table_delete_data_init(ctx, &delete_data, data->table_dest);
  if (data->have_subrec) {
    GRN_TABLE_EACH_BEGIN(ctx, data->table_dest, cursor, id_dest)
    {
      void *key_dest;
      uint32_t key_dest_size;
      void *value_dest;
      grn_table_cursor_get_key_value(ctx,
                                     cursor,
                                     &key_dest,
                                     &key_dest_size,
                                     &value_dest);
      void *value_src;
      grn_id id_src = grn_table_get_v(ctx,
                                      data->table_src,
                                      key_dest,
                                      key_dest_size,
                                      &value_src);
      if (id_src == GRN_ID_NIL) {
        delete_data.id = id_dest;
        delete_data.key = key_dest;
        delete_data.key_size = key_dest_size;
        grn_table_delete_by_id_without_lock(ctx, &delete_data);
      } else {
        grn_rset_recinfo *ri_dest = value_dest;
        grn_rset_recinfo *ri_src = value_src;
        ri_dest->score += ri_src->score * data->weight_factor;
        grn_table_setoperation_merge_columns(ctx, data, id_dest, id_src);
      }
    }
    GRN_TABLE_EACH_END(ctx, cursor);
  } else {
    GRN_TABLE_EACH_BEGIN(ctx, data->table_dest, cursor, id_dest)
    {
      void *key_dest;
      uint32_t key_dest_size = grn_table_cursor_get_key(ctx, cursor, &key_dest);
      grn_id id_src =
        grn_table_get(ctx, data->table_src, key_dest, key_dest_size);
      if (id_src == GRN_ID_NIL) {
        delete_data.id = id_dest;
        delete_data.key = key_dest;
        delete_data.key_size = key_dest_size;
        grn_table_delete_by_id_without_lock(ctx, &delete_data);
      } else {
        grn_table_setoperation_merge_columns(ctx, data, id_dest, id_src);
      }
    }
    GRN_TABLE_EACH_END(ctx, cursor);
  }
  grn_table_delete_data_fin(ctx, &delete_data);
}

static inline void
grn_table_setoperation_and_not(grn_ctx *ctx, grn_table_setoperation_data *data)
{
  GRN_TABLE_EACH_BEGIN(ctx, data->table_src, cursor, id_src)
  {
    void *key_src;
    uint32_t key_src_size = grn_table_cursor_get_key(ctx, cursor, &key_src);
    grn_table_delete(ctx, data->table_dest, key_src, key_src_size);
  }
  GRN_TABLE_EACH_END(ctx, cursor);
}

static inline void
grn_table_setoperation_adjust(grn_ctx *ctx, grn_table_setoperation_data *data)
{
  if (data->have_subrec) {
    GRN_TABLE_EACH_BEGIN(ctx, data->table_src, cursor, id_src)
    {
      void *key_src;
      uint32_t key_src_size;
      void *value_src;
      grn_table_cursor_get_key_value(ctx,
                                     cursor,
                                     &key_src,
                                     &key_src_size,
                                     &value_src);
      void *value_dest;
      grn_id id_dest = grn_table_get_v(ctx,
                                       data->table_dest,
                                       key_src,
                                       key_src_size,
                                       &value_dest);
      if (id_dest != GRN_ID_NIL) {
        grn_rset_recinfo *ri_dest = value_dest;
        grn_rset_recinfo *ri_src = value_src;
        ri_dest->score += ri_src->score * data->weight_factor;
        grn_table_setoperation_merge_columns(ctx, data, id_dest, id_src);
      }
    }
    GRN_TABLE_EACH_END(ctx, cursor);
  } else {
    if (!grn_table_setoperation_need_merge_columns(ctx, data)) {
      return;
    }
    GRN_TABLE_EACH_BEGIN(ctx, data->table_src, cursor, id_src)
    {
      void *key_src;
      uint32_t key_src_size = grn_table_cursor_get_key(ctx, cursor, &key_src);
      void *value_dest;
      grn_id id_dest = grn_table_get_v(ctx,
                                       data->table_dest,
                                       key_src,
                                       key_src_size,
                                       &value_dest);
      if (id_dest != GRN_ID_NIL) {
        grn_table_setoperation_merge_columns(ctx, data, id_dest, id_src);
      }
    }
    GRN_TABLE_EACH_END(ctx, cursor);
  }
}

grn_rc
grn_table_setoperation(
  grn_ctx *ctx, grn_obj *table1, grn_obj *table2, grn_obj *res, grn_operator op)
{
  return grn_table_setoperation_with_weight_factor(ctx,
                                                   table1,
                                                   table2,
                                                   res,
                                                   op,
                                                   1.0);
}

grn_rc
grn_table_setoperation_with_weight_factor(grn_ctx *ctx,
                                          grn_obj *table1,
                                          grn_obj *table2,
                                          grn_obj *res,
                                          grn_operator op,
                                          float weight_factor)
{
  GRN_API_ENTER;
  if (!table1) {
    ERR(GRN_INVALID_ARGUMENT, "[table][setoperation] table1 is NULL");
    GRN_API_RETURN(ctx->rc);
  }
  if (!table2) {
    ERR(GRN_INVALID_ARGUMENT, "[table][setoperation] table2 is NULL");
    GRN_API_RETURN(ctx->rc);
  }
  if (!res) {
    ERR(GRN_INVALID_ARGUMENT, "[table][setoperation] result table is NULL");
    GRN_API_RETURN(ctx->rc);
  }

  grn_table_setoperation_data data;
  data.op = op;
  data.weight_factor = weight_factor;
  if (table1 == res) {
    data.table_src = table2;
    data.table_dest = table1;
  } else {
    if (table2 == res) {
      data.table_src = table1;
      data.table_dest = table2;
    } else {
      ERR(GRN_INVALID_ARGUMENT,
          "[table][setoperation] table1 or table2 must be result table");
      GRN_API_RETURN(ctx->rc);
    }
  }
  data.have_subrec =
    ((DB_OBJ(data.table_src)->header.flags & GRN_OBJ_WITH_SUBREC) &&
     (DB_OBJ(data.table_dest)->header.flags & GRN_OBJ_WITH_SUBREC));
  grn_table_setoperation_data_init(ctx, &data);
  switch (op) {
  case GRN_OP_OR:
    grn_table_setoperation_or(ctx, &data);
    break;
  case GRN_OP_AND:
    grn_table_setoperation_and(ctx, &data);
    break;
  case GRN_OP_AND_NOT:
    grn_table_setoperation_and_not(ctx, &data);
    break;
  case GRN_OP_ADJUST:
    grn_table_setoperation_adjust(ctx, &data);
    break;
  default:
    break;
  }
  grn_table_setoperation_data_fin(ctx, &data);
  GRN_API_RETURN(ctx->rc);
}

grn_rc
grn_table_difference(
  grn_ctx *ctx, grn_obj *table1, grn_obj *table2, grn_obj *res1, grn_obj *res2)
{
  void *key = NULL;
  uint32_t key_size = 0;
  if (table1 != res1 || table2 != res2) {
    return GRN_INVALID_ARGUMENT;
  }
  grn_table_delete_data data1;
  grn_table_delete_data_init(ctx, &data1, table1);
  grn_table_delete_data data2;
  grn_table_delete_data_init(ctx, &data2, table2);
  if (grn_table_size(ctx, table1) > grn_table_size(ctx, table2)) {
    GRN_TABLE_EACH(ctx, table2, 0, 0, id, &key, &key_size, NULL, {
      grn_id id1;
      if ((id1 = grn_table_get(ctx, table1, key, key_size))) {
        data1.id = id1;
        data1.key = key;
        data1.key_size = key_size;
        grn_table_delete_by_id_without_lock(ctx, &data1);
        data2.id = id;
        data2.key = key;
        data2.key_size = key_size;
        grn_table_delete_by_id_without_lock(ctx, &data2);
      }
    });
  } else {
    GRN_TABLE_EACH(ctx, table1, 0, 0, id, &key, &key_size, NULL, {
      grn_id id2;
      if ((id2 = grn_table_get(ctx, table2, key, key_size))) {
        data1.id = id;
        data1.key = key;
        data1.key_size = key_size;
        grn_table_delete_by_id_without_lock(ctx, &data1);
        data2.id = id2;
        data2.key = key;
        data2.key_size = key_size;
        grn_table_delete_by_id_without_lock(ctx, &data2);
      }
    });
  }
  grn_table_delete_data_fin(ctx, &data1);
  grn_table_delete_data_fin(ctx, &data2);
  return GRN_SUCCESS;
}

static grn_obj *
grn_obj_get_accessor(grn_ctx *ctx,
                     grn_obj *obj,
                     const char *name,
                     uint32_t name_size);

static grn_obj *
grn_obj_column_(grn_ctx *ctx,
                grn_obj *table,
                const char *name,
                uint32_t name_size)
{
  grn_id table_id = DB_OBJ(table)->id;
  grn_obj *column = NULL;

  if (table_id & GRN_OBJ_TMP_OBJECT) {
    char column_name[GRN_TABLE_MAX_KEY_SIZE];
    void *value = NULL;
    grn_snprintf(column_name,
                 GRN_TABLE_MAX_KEY_SIZE,
                 GRN_TABLE_MAX_KEY_SIZE,
                 "%u%c%.*s",
                 table_id,
                 GRN_DB_DELIMITER,
                 (int)name_size,
                 name);
    grn_ctx *target_ctx = ctx;
    while (target_ctx->impl->parent) {
      target_ctx = target_ctx->impl->parent;
    }
    grn_pat_get(target_ctx,
                target_ctx->impl->temporary_columns,
                column_name,
                strlen(column_name),
                &value);
    if (value) {
      column = *((grn_obj **)value);
      DB_OBJ(column)->reference_count++;
    }
  } else {
    char buf[GRN_TABLE_MAX_KEY_SIZE];
    int len = grn_obj_name(ctx, table, buf, GRN_TABLE_MAX_KEY_SIZE);
    if (len) {
      buf[len++] = GRN_DB_DELIMITER;
      if (len + name_size <= GRN_TABLE_MAX_KEY_SIZE) {
        grn_obj alias_name_buffer;
        grn_memcpy(buf + len, name, name_size);
        GRN_TEXT_INIT(&alias_name_buffer, 0);
        column = grn_alias_resolve(ctx,
                                   buf,
                                   len + name_size,
                                   &alias_name_buffer,
                                   GRN_TRUE);
        if (!column && GRN_TEXT_LEN(&alias_name_buffer) > 0) {
          const size_t delimiter_len = 1;
          const size_t table_name_len = len - delimiter_len;
          const char *alias_name = GRN_TEXT_VALUE(&alias_name_buffer);
          size_t alias_name_size = GRN_TEXT_LEN(&alias_name_buffer);
          if (alias_name_size > (size_t)len &&
              alias_name[table_name_len] == GRN_DB_DELIMITER &&
              strncmp(alias_name, buf, table_name_len) == 0) {
            alias_name += len;
            alias_name_size -= len;
          }
          column =
            grn_obj_get_accessor(ctx, table, alias_name, alias_name_size);
        }
        GRN_OBJ_FIN(ctx, &alias_name_buffer);
      } else {
        ERR(GRN_INVALID_ARGUMENT, "name is too long");
      }
    }
  }

  return column;
}

grn_obj *
grn_obj_column(grn_ctx *ctx,
               grn_obj *table,
               const char *name,
               uint32_t name_size)
{
  grn_obj *column = NULL;
  GRN_API_ENTER;
  if (GRN_OBJ_TABLEP(table)) {
    if (grn_db_check_name(ctx, name, name_size) == GRN_SUCCESS) {
      column = grn_obj_column_(ctx, table, name, name_size);
    }
    if (!column) {
      column = grn_obj_get_accessor(ctx, table, name, name_size);
    }
  } else if (GRN_ACCESSORP(table)) {
    column = grn_obj_get_accessor(ctx, table, name, name_size);
  }
  GRN_API_RETURN(column);
}

int
grn_table_columns(grn_ctx *ctx,
                  grn_obj *table,
                  const char *name,
                  unsigned int name_size,
                  grn_obj *res)
{
  int n = 0;
  grn_id id;

  GRN_API_ENTER;

  if (!GRN_OBJ_TABLEP(table)) {
    GRN_API_RETURN(n);
  }

  id = DB_OBJ(table)->id;

  if (id == GRN_ID_NIL) {
    GRN_API_RETURN(n);
  }

  if (id & GRN_OBJ_TMP_OBJECT) {
    char search_key[GRN_TABLE_MAX_KEY_SIZE];
    grn_pat_cursor *cursor;
    grn_snprintf(search_key,
                 GRN_TABLE_MAX_KEY_SIZE,
                 GRN_TABLE_MAX_KEY_SIZE,
                 "%u%c%.*s",
                 id,
                 GRN_DB_DELIMITER,
                 name_size,
                 name);
    grn_ctx *target_ctx = ctx;
    while (target_ctx->impl->parent) {
      target_ctx = target_ctx->impl->parent;
    }
    cursor = grn_pat_cursor_open(target_ctx,
                                 target_ctx->impl->temporary_columns,
                                 search_key,
                                 strlen(search_key),
                                 NULL,
                                 0,
                                 0,
                                 -1,
                                 GRN_CURSOR_PREFIX);
    if (cursor) {
      grn_id column_id;
      while ((column_id = grn_pat_cursor_next(target_ctx, cursor)) !=
             GRN_ID_NIL) {
        column_id |= GRN_OBJ_TMP_OBJECT | GRN_OBJ_TMP_COLUMN;
        grn_hash_add(ctx,
                     (grn_hash *)res,
                     &column_id,
                     sizeof(grn_id),
                     NULL,
                     NULL);
        n++;
      }
      grn_pat_cursor_close(target_ctx, cursor);
    }
  } else {
    grn_db *s = (grn_db *)DB_OBJ(table)->db;
    if (s->keys) {
      grn_obj bulk;
      GRN_TEXT_INIT(&bulk, 0);
      grn_table_get_key2(ctx, s->keys, id, &bulk);
      GRN_TEXT_PUTC(ctx, &bulk, GRN_DB_DELIMITER);
      grn_bulk_write(ctx, &bulk, name, name_size);
      grn_table_search(ctx,
                       s->keys,
                       GRN_BULK_HEAD(&bulk),
                       GRN_BULK_VSIZE(&bulk),
                       GRN_OP_PREFIX,
                       res,
                       GRN_OP_OR);
      grn_obj_close(ctx, &bulk);
      n = grn_table_size(ctx, res);
    }
  }

  GRN_API_RETURN(n);
}

const char *
_grn_table_key(grn_ctx *ctx, grn_obj *table, grn_id id, uint32_t *key_size)
{
  GRN_ASSERT(table);
  if (table->header.type == GRN_DB) {
    table = ((grn_db *)table)->keys;
  }
  switch (table->header.type) {
  case GRN_TABLE_HASH_KEY:
    return _grn_hash_key(ctx, (grn_hash *)table, id, key_size);
  case GRN_TABLE_PAT_KEY:
    return _grn_pat_key(ctx, (grn_pat *)table, id, key_size);
  case GRN_TABLE_DAT_KEY:
    return _grn_dat_key(ctx, (grn_dat *)table, id, key_size);
  case GRN_TABLE_NO_KEY:
    {
      grn_array *a = (grn_array *)table;
      const char *v;
      if (a->obj.header.domain && a->value_size &&
          (v = _grn_array_get_value(ctx, a, id))) {
        *key_size = a->value_size;
        return v;
      } else {
        *key_size = 0;
      }
    }
    break;
  }
  return NULL;
}

/* column */

grn_obj *
grn_column_create(grn_ctx *ctx,
                  grn_obj *table,
                  const char *name,
                  unsigned int name_size,
                  const char *path,
                  grn_column_flags flags,
                  grn_obj *type)
{
  grn_db *s;
  uint32_t value_size;
  grn_obj *db, *res = NULL;
  grn_id id = GRN_ID_NIL;
  grn_id range = GRN_ID_NIL;
  grn_id domain = GRN_ID_NIL;
  bool is_persistent_table;
  char fullname[GRN_TABLE_MAX_KEY_SIZE];
  unsigned int fullname_size;
  char buffer[PATH_MAX];

  GRN_API_ENTER;
  if (!table) {
    ERR(GRN_INVALID_ARGUMENT, "[column][create] table is missing");
    goto exit;
  }
  if (!type) {
    ERR(GRN_INVALID_ARGUMENT, "[column][create] type is missing");
    goto exit;
  }
  if (!name || !name_size) {
    ERR(GRN_INVALID_ARGUMENT, "[column][create] name is missing");
    goto exit;
  }
  db = DB_OBJ(table)->db;
  s = (grn_db *)db;
  if (!GRN_DB_P(s)) {
    int table_name_len;
    char table_name[GRN_TABLE_MAX_KEY_SIZE];
    table_name_len =
      grn_obj_name(ctx, table, table_name, GRN_TABLE_MAX_KEY_SIZE);
    ERR(GRN_INVALID_ARGUMENT,
        "[column][create] invalid db assigned: <%.*s>.<%.*s>",
        table_name_len,
        table_name,
        name_size,
        name);
    goto exit;
  }

  if (grn_db_check_name(ctx, name, name_size)) {
    GRN_DB_CHECK_NAME_ERR("[column][create]", name, name_size);
    goto exit;
  }

  domain = DB_OBJ(table)->id;
  is_persistent_table = !(domain & GRN_OBJ_TMP_OBJECT);

  if (!domain) {
    ERR(GRN_FUNCTION_NOT_IMPLEMENTED,
        "[column][create] [todo] table-less column isn't supported yet");
    goto exit;
  }

  {
    int table_name_len;
    if (is_persistent_table) {
      table_name_len = grn_table_get_key(ctx,
                                         s->keys,
                                         domain,
                                         fullname,
                                         GRN_TABLE_MAX_KEY_SIZE);
    } else {
      grn_snprintf(fullname,
                   GRN_TABLE_MAX_KEY_SIZE,
                   GRN_TABLE_MAX_KEY_SIZE,
                   "%u",
                   domain);
      table_name_len = strlen(fullname);
    }
    if (name_size + 1 + table_name_len > GRN_TABLE_MAX_KEY_SIZE) {
      ERR(GRN_INVALID_ARGUMENT,
          "[column][create] too long column name: required name_size(%d) < %d"
          ": <%.*s>.<%.*s>",
          name_size,
          GRN_TABLE_MAX_KEY_SIZE - 1 - table_name_len,
          table_name_len,
          fullname,
          name_size,
          name);
      goto exit;
    }
    fullname[table_name_len] = GRN_DB_DELIMITER;
    grn_memcpy(fullname + table_name_len + 1, name, name_size);
    fullname_size = table_name_len + 1 + name_size;
  }

  range = DB_OBJ(type)->id;
  switch (type->header.type) {
  case GRN_TYPE:
    {
      grn_db_obj *t = (grn_db_obj *)type;
      flags |= t->header.flags & ~GRN_OBJ_KEY_MASK;
      value_size = GRN_TYPE_SIZE(t);
    }
    break;
  case GRN_TABLE_HASH_KEY:
  case GRN_TABLE_PAT_KEY:
  case GRN_TABLE_DAT_KEY:
  case GRN_TABLE_NO_KEY:
    value_size = sizeof(grn_id);
    break;
  default:
    /*
    if (type == grn_type_any) {
      value_size = sizeof(grn_id) + sizeof(grn_id);
    }
    */
    value_size = sizeof(grn_id);
  }

  if (is_persistent_table) {
    id = grn_obj_register(ctx, db, fullname, fullname_size);
    if (ERRP(ctx, GRN_ERROR)) {
      goto exit;
    }

    {
      uint32_t table_name_size = 0;
      const char *table_name;
      table_name = _grn_table_key(ctx, ctx->impl->db, domain, &table_name_size);
      GRN_LOG(ctx,
              GRN_LOG_NOTICE,
              "DDL:%u:column_create %.*s %.*s",
              id,
              table_name_size,
              table_name,
              name_size,
              name);
    }
  } else {
    grn_ctx *target_ctx = ctx;
    while (target_ctx->impl->parent) {
      target_ctx = target_ctx->impl->parent;
    }
    if (target_ctx != ctx) {
      CRITICAL_SECTION_ENTER(target_ctx->impl->temporary_objects_lock);
    }
    int added;
    id = grn_pat_add(target_ctx,
                     target_ctx->impl->temporary_columns,
                     fullname,
                     fullname_size,
                     NULL,
                     &added);
    if (target_ctx != ctx) {
      CRITICAL_SECTION_LEAVE(target_ctx->impl->temporary_objects_lock);
    }
    if (!id) {
      ERR(GRN_NO_MEMORY_AVAILABLE,
          "[column][create][temporary] "
          "failed to register temporary column name: <%.*s>",
          fullname_size,
          fullname);
      goto exit;
    } else if (!added) {
      id = GRN_ID_NIL;
      ERR(GRN_NO_MEMORY_AVAILABLE,
          "[column][create][temporary] already used name was assigned: <%.*s>",
          fullname_size,
          fullname);
      goto exit;
    }
    id |= GRN_OBJ_TMP_OBJECT | GRN_OBJ_TMP_COLUMN;
  }

  if (is_persistent_table && flags & GRN_OBJ_PERSISTENT) {
    if (!path) {
      if (GRN_DB_PERSISTENT_P(db)) {
        grn_db_generate_pathname(ctx, db, id, buffer);
        path = buffer;
      } else {
        int table_name_len;
        char table_name[GRN_TABLE_MAX_KEY_SIZE];
        table_name_len =
          grn_obj_name(ctx, table, table_name, GRN_TABLE_MAX_KEY_SIZE);
        ERR(GRN_INVALID_ARGUMENT,
            "[column][create] path not assigned for persistent column"
            ": <%.*s>.<%.*s>",
            table_name_len,
            table_name,
            name_size,
            name);
        goto exit;
      }
    } else {
      flags |= GRN_OBJ_CUSTOM_NAME;
    }
  } else {
    if (path) {
      int table_name_len;
      char table_name[GRN_TABLE_MAX_KEY_SIZE];
      table_name_len =
        grn_obj_name(ctx, table, table_name, GRN_TABLE_MAX_KEY_SIZE);
      ERR(GRN_INVALID_ARGUMENT,
          "[column][create] path assigned for temporary column"
          ": <%.*s>.<%.*s>",
          table_name_len,
          table_name,
          name_size,
          name);
      goto exit;
    }
  }
  switch (flags & GRN_OBJ_COLUMN_TYPE_MASK) {
  case GRN_OBJ_COLUMN_SCALAR:
    if ((flags & GRN_OBJ_KEY_VAR_SIZE) || value_size > sizeof(int64_t)) {
      res = (grn_obj *)grn_ja_create(ctx, path, value_size, flags);
    } else {
      res = (grn_obj *)grn_ra_create(ctx, path, value_size, flags);
    }
    break;
  case GRN_OBJ_COLUMN_VECTOR:
    res = (grn_obj *)grn_ja_create(ctx, path, value_size * 30 /*todo*/, flags);
    // todo : zlib support
    break;
  case GRN_OBJ_COLUMN_INDEX:
    res = (grn_obj *)
      grn_ii_create(ctx, path, table, flags); // todo : ii layout support
    break;
  }
  if (res) {
    DB_OBJ(res)->header.domain = domain;
    DB_OBJ(res)->header.impl_flags = 0;
    DB_OBJ(res)->range = range;
    DB_OBJ(res)->header.flags = flags;
    res->header.flags = flags;
    if (grn_db_obj_init(ctx, db, id, DB_OBJ(res)) != GRN_SUCCESS) {
      grn_obj_remove_internal(ctx, res, 0);
      res = NULL;
      goto exit;
    }
    if (grn_obj_is_persistent(ctx, res)) {
      grn_obj *space;
      space = ctx->impl->temporary_open_spaces.current;
      if (space) {
        GRN_PTR_PUT(ctx, space, res);
      }
    }
    grn_ctx_impl_columns_cache_delete(ctx, domain);
    grn_obj_touch(ctx, res, NULL);
  }
exit:
  if (!res && id) {
    grn_obj_delete_by_id(ctx, db, id, GRN_TRUE);
  }
  GRN_API_RETURN(res);
}

grn_obj *
grn_column_create_similar(grn_ctx *ctx,
                          grn_obj *table,
                          const char *name,
                          uint32_t name_size,
                          const char *path,
                          grn_obj *base_column)
{
  GRN_API_ENTER;
  grn_obj *column = grn_column_create_similar_id_map(ctx,
                                                     table,
                                                     name,
                                                     name_size,
                                                     path,
                                                     base_column,
                                                     NULL);
  GRN_API_RETURN(column);
}

grn_obj *
grn_column_open(grn_ctx *ctx,
                grn_obj *table,
                const char *name,
                unsigned int name_size,
                const char *path,
                grn_obj *type)
{
  grn_id domain;
  grn_obj *res = NULL;
  grn_db *s;
  char fullname[GRN_TABLE_MAX_KEY_SIZE];
  GRN_API_ENTER;
  if (!table || !type || !name || !name_size) {
    ERR(GRN_INVALID_ARGUMENT, "missing type or name");
    goto exit;
  }
  s = (grn_db *)DB_OBJ(table)->db;
  if (!GRN_DB_P(s)) {
    ERR(GRN_INVALID_ARGUMENT, "invalid db assigned");
    goto exit;
  }
  if (grn_db_check_name(ctx, name, name_size)) {
    GRN_DB_CHECK_NAME_ERR("[column][open]", name, name_size);
    goto exit;
  }
  if ((domain = DB_OBJ(table)->id)) {
    int len =
      grn_table_get_key(ctx, s->keys, domain, fullname, GRN_TABLE_MAX_KEY_SIZE);
    if (name_size + 1 + len > GRN_TABLE_MAX_KEY_SIZE) {
      ERR(GRN_INVALID_ARGUMENT, "too long column name");
      goto exit;
    }
    fullname[len] = GRN_DB_DELIMITER;
    grn_memcpy(fullname + len + 1, name, name_size);
    name_size += len + 1;
  } else {
    ERR(GRN_INVALID_ARGUMENT, "todo : not supported yet");
    goto exit;
  }
  res = grn_ctx_get(ctx, fullname, name_size);
  if (res) {
    const char *path2 = grn_obj_path(ctx, res);
    if (path && (!path2 || strcmp(path, path2))) {
      goto exit;
    }
  } else if (path) {
    uint32_t dbtype = grn_io_detect_type(ctx, path);
    if (!dbtype) {
      goto exit;
    }
    switch (dbtype) {
    case GRN_COLUMN_VAR_SIZE:
      res = (grn_obj *)grn_ja_open(ctx, path);
      break;
    case GRN_COLUMN_FIX_SIZE:
      res = (grn_obj *)grn_ra_open(ctx, path);
      break;
    case GRN_COLUMN_INDEX:
      res = (grn_obj *)grn_ii_open(ctx, path, table);
      break;
    }
    if (res) {
      grn_id id = grn_obj_register(ctx, (grn_obj *)s, fullname, name_size);
      DB_OBJ(res)->header.domain = domain;
      DB_OBJ(res)->range = DB_OBJ(type)->id;
      res->header.flags |= GRN_OBJ_CUSTOM_NAME;
      grn_db_obj_init(ctx, (grn_obj *)s, id, DB_OBJ(res));
    }
  }
exit:
  GRN_API_RETURN(res);
}

/**** accessor ****/

static grn_accessor *
grn_accessor_new_key(grn_ctx *ctx, grn_obj *table)
{
  grn_accessor *accessor = grn_accessor_new(ctx);
  if (!accessor) {
    return accessor;
  }
  grn_obj_refer(ctx, table);
  accessor->obj = table;
  accessor->action = GRN_ACCESSOR_GET_KEY;
  return accessor;
}

static inline void
grn_accessor_refer(grn_ctx *ctx, grn_obj *accessor)
{
  ((grn_accessor *)accessor)->reference_count++;
}

static inline bool
grn_obj_get_accessor_rset_value(grn_ctx *ctx,
                                grn_obj *obj,
                                grn_accessor **res,
                                uint8_t action)
{
  bool succeeded = false;
  grn_accessor **rp;

  for (rp = res; GRN_TRUE; rp = &(*rp)->next) {
    *rp = grn_accessor_new(ctx);
    (*rp)->obj = obj;

#define CHECK_GROUP_CALC_FLAG(flag)                                            \
  do {                                                                         \
    if (GRN_TABLE_IS_GROUPED(obj)) {                                           \
      grn_table_group_flags flags;                                             \
      flags = DB_OBJ(obj)->group.flags;                                        \
      if (flags & flag) {                                                      \
        succeeded = true;                                                      \
        (*rp)->action = action;                                                \
        goto exit;                                                             \
      }                                                                        \
    }                                                                          \
  } while (GRN_FALSE)
    switch (action) {
    case GRN_ACCESSOR_GET_SCORE:
      if (DB_OBJ(obj)->header.flags & GRN_OBJ_WITH_SUBREC) {
        (*rp)->action = action;
        succeeded = true;
        goto exit;
      }
      break;
    case GRN_ACCESSOR_GET_MAX:
      CHECK_GROUP_CALC_FLAG(GRN_TABLE_GROUP_CALC_MAX);
      break;
    case GRN_ACCESSOR_GET_MIN:
      CHECK_GROUP_CALC_FLAG(GRN_TABLE_GROUP_CALC_MIN);
      break;
    case GRN_ACCESSOR_GET_SUM:
      CHECK_GROUP_CALC_FLAG(GRN_TABLE_GROUP_CALC_SUM);
      break;
    case GRN_ACCESSOR_GET_AVG:
      CHECK_GROUP_CALC_FLAG(GRN_TABLE_GROUP_CALC_AVG);
      break;
    case GRN_ACCESSOR_GET_MEAN:
      CHECK_GROUP_CALC_FLAG(GRN_TABLE_GROUP_CALC_MEAN);
      break;
    case GRN_ACCESSOR_GET_NSUBRECS:
      if (GRN_TABLE_IS_GROUPED(obj)) {
        (*rp)->action = action;
        succeeded = true;
        goto exit;
      }
      break;
    }
#undef CHECK_GROUP_CALC_FLAG

    switch (obj->header.type) {
    case GRN_TABLE_PAT_KEY:
    case GRN_TABLE_DAT_KEY:
    case GRN_TABLE_HASH_KEY:
      (*rp)->action = GRN_ACCESSOR_GET_KEY;
      break;
    case GRN_TABLE_NO_KEY:
      if (!obj->header.domain) {
        goto exit;
      }
      (*rp)->action = GRN_ACCESSOR_GET_VALUE;
      break;
    default:
      /* lookup failed */
      goto exit;
    }
    if (!(obj = grn_ctx_at(ctx, obj->header.domain))) {
      goto exit;
    }
  }

exit:
  if (!succeeded) {
    grn_obj_close(ctx, (grn_obj *)*res);
    *res = NULL;
  }

  return succeeded;
}

static grn_obj *
grn_obj_get_accessor(grn_ctx *ctx,
                     grn_obj *obj,
                     const char *name,
                     uint32_t name_size)
{
  grn_accessor *res = NULL, **rp = NULL, **rp0 = NULL;
  grn_bool is_chained = GRN_FALSE;
  bool obj_is_referred = false;
  if (!obj) {
    return NULL;
  }
  GRN_API_ENTER;
  if (obj->header.type == GRN_ACCESSOR) {
    is_chained = GRN_TRUE;
    for (rp0 = (grn_accessor **)&obj; *rp0; rp0 = &(*rp0)->next) {
      res = *rp0;
    }
    switch (res->action) {
    case GRN_ACCESSOR_GET_KEY:
      obj = grn_ctx_at(ctx, res->obj->header.domain);
      obj_is_referred = true;
      break;
    case GRN_ACCESSOR_GET_VALUE:
    case GRN_ACCESSOR_GET_SCORE:
    case GRN_ACCESSOR_GET_NSUBRECS:
    case GRN_ACCESSOR_GET_MAX:
    case GRN_ACCESSOR_GET_MIN:
    case GRN_ACCESSOR_GET_SUM:
    case GRN_ACCESSOR_GET_AVG:
    case GRN_ACCESSOR_GET_MEAN:
      obj = grn_ctx_at(ctx, DB_OBJ(res->obj)->range);
      obj_is_referred = true;
      break;
    case GRN_ACCESSOR_GET_COLUMN_VALUE:
      obj = grn_ctx_at(ctx, DB_OBJ(res->obj)->range);
      obj_is_referred = true;
      break;
    case GRN_ACCESSOR_LOOKUP:
      /* todo */
      break;
    case GRN_ACCESSOR_FUNCALL:
      /* todo */
      break;
    }
  }
  if (!obj) {
    res = NULL;
    goto exit;
  }
  {
    size_t len;
    const char *sp, *se = name + name_size;
    if (*name == GRN_DB_DELIMITER) {
      name++;
    }
    for (sp = name; (len = grn_charlen(ctx, sp, se)); sp += len) {
      if (*sp == GRN_DB_DELIMITER) {
        break;
      }
    }
    if (!(len = sp - name)) {
      goto exit;
    }
    if (*name == GRN_DB_PSEUDO_COLUMN_PREFIX) { /* pseudo column */
      int done = 0;
      if (len < 2) {
        goto exit;
      }
      switch (name[1]) {
      case 'k': /* key */
        if (len != GRN_COLUMN_NAME_KEY_LEN ||
            memcmp(name, GRN_COLUMN_NAME_KEY, GRN_COLUMN_NAME_KEY_LEN)) {
          goto exit;
        }
        for (rp = &res; !done; rp = &(*rp)->next) {
          *rp = grn_accessor_new(ctx);
          if (!obj_is_referred) {
            grn_obj_refer(ctx, obj);
            obj_is_referred = true;
          }
          (*rp)->obj = obj;
          if (GRN_TABLE_IS_MULTI_KEYS_GROUPED(obj)) {
            (*rp)->action = GRN_ACCESSOR_GET_KEY;
            done++;
            break;
          }
          if (!(obj = grn_ctx_at(ctx, obj->header.domain))) {
            grn_obj_close(ctx, (grn_obj *)res);
            res = NULL;
            goto exit;
          }
          switch (obj->header.type) {
          case GRN_DB:
            (*rp)->action = GRN_ACCESSOR_GET_KEY;
            rp = &(*rp)->next;
            *rp = grn_accessor_new(ctx);
            (*rp)->obj = obj;
            (*rp)->action = GRN_ACCESSOR_GET_DB_OBJ;
            done++;
            break;
          case GRN_TYPE:
            (*rp)->action = GRN_ACCESSOR_GET_KEY;
            done++;
            break;
          case GRN_TABLE_PAT_KEY:
          case GRN_TABLE_DAT_KEY:
          case GRN_TABLE_HASH_KEY:
            (*rp)->action = GRN_ACCESSOR_GET_KEY;
            break;
          case GRN_TABLE_NO_KEY:
            if (obj->header.domain) {
              (*rp)->action = GRN_ACCESSOR_GET_VALUE;
              break;
            }
            /* fallthru */
          default:
            /* lookup failed */
            grn_obj_close(ctx, (grn_obj *)res);
            res = NULL;
            grn_obj_unref(ctx, obj);
            goto exit;
          }
        }
        break;
      case 'i': /* id */
        if (len != GRN_COLUMN_NAME_ID_LEN ||
            memcmp(name, GRN_COLUMN_NAME_ID, GRN_COLUMN_NAME_ID_LEN)) {
          goto exit;
        }
        for (rp = &res; !done; rp = &(*rp)->next) {
          *rp = grn_accessor_new(ctx);
          if (!obj_is_referred) {
            grn_obj_refer(ctx, obj);
            obj_is_referred = true;
          }
          (*rp)->obj = obj;
          if (!obj->header.domain) {
            (*rp)->action = GRN_ACCESSOR_GET_ID;
            done++;
          } else {
            if (!(obj = grn_ctx_at(ctx, obj->header.domain))) {
              grn_obj_close(ctx, (grn_obj *)res);
              res = NULL;
              goto exit;
            }
            switch (obj->header.type) {
            case GRN_DB:
            case GRN_TYPE:
              (*rp)->action = GRN_ACCESSOR_GET_ID;
              done++;
              break;
            case GRN_TABLE_PAT_KEY:
            case GRN_TABLE_DAT_KEY:
            case GRN_TABLE_HASH_KEY:
            case GRN_TABLE_NO_KEY:
              (*rp)->action = GRN_ACCESSOR_GET_KEY;
              break;
            default:
              /* lookup failed */
              grn_obj_close(ctx, (grn_obj *)res);
              res = NULL;
              grn_obj_unref(ctx, obj);
              goto exit;
            }
          }
        }
        break;
      case 'v': /* value */
        if (len != GRN_COLUMN_NAME_VALUE_LEN ||
            memcmp(name, GRN_COLUMN_NAME_VALUE, GRN_COLUMN_NAME_VALUE_LEN)) {
          goto exit;
        }
        for (rp = &res; !done; rp = &(*rp)->next) {
          *rp = grn_accessor_new(ctx);
          if (!obj_is_referred) {
            grn_obj_refer(ctx, obj);
            obj_is_referred = true;
          }
          (*rp)->obj = obj;
          if (!obj->header.domain) {
            if (DB_OBJ((*rp)->obj)->range) {
              (*rp)->action = GRN_ACCESSOR_GET_VALUE;
              done++;
            } else {
              grn_obj_close(ctx, (grn_obj *)res);
              res = NULL;
              goto exit;
            }
            done++;
          } else {
            if (!(obj = grn_ctx_at(ctx, obj->header.domain))) {
              grn_obj_close(ctx, (grn_obj *)res);
              res = NULL;
              goto exit;
            }
            switch (obj->header.type) {
            case GRN_TYPE:
              if (DB_OBJ((*rp)->obj)->range) {
                (*rp)->action = GRN_ACCESSOR_GET_VALUE;
                done++;
              } else {
                grn_obj_close(ctx, (grn_obj *)res);
                res = NULL;
                goto exit;
              }
              break;
            case GRN_TABLE_PAT_KEY:
            case GRN_TABLE_DAT_KEY:
            case GRN_TABLE_HASH_KEY:
            case GRN_TABLE_NO_KEY:
              (*rp)->action = GRN_ACCESSOR_GET_KEY;
              break;
            default:
              /* lookup failed */
              grn_obj_close(ctx, (grn_obj *)res);
              res = NULL;
              grn_obj_unref(ctx, obj);
              goto exit;
            }
          }
        }
        break;
      case 's': /* score, sum */
        if (!obj_is_referred) {
          grn_obj_refer(ctx, obj);
          obj_is_referred = true;
        }
        if (len == GRN_COLUMN_NAME_SCORE_LEN &&
            memcmp(name, GRN_COLUMN_NAME_SCORE, GRN_COLUMN_NAME_SCORE_LEN) ==
              0) {
          if (!grn_obj_get_accessor_rset_value(ctx,
                                               obj,
                                               &res,
                                               GRN_ACCESSOR_GET_SCORE)) {
            goto exit;
          }
        } else if (len == GRN_COLUMN_NAME_SUM_LEN &&
                   memcmp(name, GRN_COLUMN_NAME_SUM, GRN_COLUMN_NAME_SUM_LEN) ==
                     0) {
          if (!grn_obj_get_accessor_rset_value(ctx,
                                               obj,
                                               &res,
                                               GRN_ACCESSOR_GET_SUM)) {
            goto exit;
          }
        } else {
          grn_obj_unref(ctx, obj);
          goto exit;
        }
        break;
      case 'n': /* nsubrecs */
        if (len != GRN_COLUMN_NAME_NSUBRECS_LEN ||
            memcmp(name,
                   GRN_COLUMN_NAME_NSUBRECS,
                   GRN_COLUMN_NAME_NSUBRECS_LEN)) {
          goto exit;
        }
        if (!obj_is_referred) {
          grn_obj_refer(ctx, obj);
          obj_is_referred = true;
        }
        if (!grn_obj_get_accessor_rset_value(ctx,
                                             obj,
                                             &res,
                                             GRN_ACCESSOR_GET_NSUBRECS)) {
          goto exit;
        }
        break;
      case 'm': /* max, mean, min */
        if (!obj_is_referred) {
          grn_obj_refer(ctx, obj);
          obj_is_referred = true;
        }
        if (len == GRN_COLUMN_NAME_MAX_LEN &&
            memcmp(name, GRN_COLUMN_NAME_MAX, GRN_COLUMN_NAME_MAX_LEN) == 0) {
          if (!grn_obj_get_accessor_rset_value(ctx,
                                               obj,
                                               &res,
                                               GRN_ACCESSOR_GET_MAX)) {
            goto exit;
          }
        } else if (len == GRN_COLUMN_NAME_MEAN_LEN &&
                   memcmp(name,
                          GRN_COLUMN_NAME_MEAN,
                          GRN_COLUMN_NAME_MEAN_LEN) == 0) {
          if (!grn_obj_get_accessor_rset_value(ctx,
                                               obj,
                                               &res,
                                               GRN_ACCESSOR_GET_MEAN)) {
            goto exit;
          }
        } else if (len == GRN_COLUMN_NAME_MIN_LEN &&
                   memcmp(name, GRN_COLUMN_NAME_MIN, GRN_COLUMN_NAME_MIN_LEN) ==
                     0) {
          if (!grn_obj_get_accessor_rset_value(ctx,
                                               obj,
                                               &res,
                                               GRN_ACCESSOR_GET_MIN)) {
            goto exit;
          }
        } else {
          grn_obj_unref(ctx, obj);
          goto exit;
        }
        break;
      case 'a': /* avg */
        if (!obj_is_referred) {
          grn_obj_refer(ctx, obj);
          obj_is_referred = true;
        }
        if (len == GRN_COLUMN_NAME_AVG_LEN &&
            memcmp(name, GRN_COLUMN_NAME_AVG, GRN_COLUMN_NAME_AVG_LEN) == 0) {
          if (!grn_obj_get_accessor_rset_value(ctx,
                                               obj,
                                               &res,
                                               GRN_ACCESSOR_GET_AVG)) {
            goto exit;
          }
        } else {
          grn_obj_unref(ctx, obj);
          goto exit;
        }
        break;
      default:
        res = NULL;
        goto exit;
      }
    } else {
      /* if obj->header.type == GRN_TYPE ... lookup table */
      for (rp = &res;; rp = &(*rp)->next) {
        grn_obj *column = grn_obj_column_(ctx, obj, name, len);
        if (column) {
          *rp = grn_accessor_new(ctx);
          (*rp)->obj = column;
          /*
          switch (column->header.type) {
          case GRN_COLUMN_VAR_SIZE :
            break;
          case GRN_COLUMN_FIX_SIZE :
            break;
          case GRN_COLUMN_INDEX :
            break;
          }
          */
          (*rp)->action = GRN_ACCESSOR_GET_COLUMN_VALUE;
          if (obj_is_referred) {
            grn_obj_unref(ctx, obj);
            obj_is_referred = false;
          }
          break;
        } else {
          grn_id next_obj_id;
          next_obj_id = obj->header.domain;
          if (!next_obj_id) {
            // ERR(GRN_INVALID_ARGUMENT, "no such column: <%s>", name);
            if (obj_is_referred) {
              grn_obj_unref(ctx, obj);
            }
            if (!is_chained) {
              grn_obj_close(ctx, (grn_obj *)res);
            }
            res = NULL;
            goto exit;
          }
          *rp = grn_accessor_new(ctx);
          if (!obj_is_referred) {
            grn_obj_refer(ctx, obj);
            obj_is_referred = true;
          }
          (*rp)->obj = obj;
          obj = grn_ctx_at(ctx, next_obj_id);
          if (!obj) {
            grn_obj_close(ctx, (grn_obj *)res);
            res = NULL;
            goto exit;
          }
          switch (obj->header.type) {
          case GRN_TABLE_PAT_KEY:
          case GRN_TABLE_DAT_KEY:
          case GRN_TABLE_HASH_KEY:
          case GRN_TABLE_NO_KEY:
            (*rp)->action = GRN_ACCESSOR_GET_KEY;
            break;
          default:
            /* lookup failed */
            grn_obj_close(ctx, (grn_obj *)res);
            res = NULL;
            grn_obj_unref(ctx, obj);
            goto exit;
          }
        }
      }
    }
    if (sp != se) {
      if (!grn_obj_get_accessor(ctx, (grn_obj *)res, sp, se - sp)) {
        if (!is_chained) {
          grn_obj_close(ctx, (grn_obj *)res);
          res = NULL;
          goto exit;
        }
      }
    }
  }
  if (rp0) {
    *rp0 = res;
  }
exit:
  GRN_API_RETURN((grn_obj *)res);
}

static inline bool
grn_column_is_vector(grn_ctx *ctx, grn_obj *column)
{
  grn_obj_flags type;

  if (column->header.type != GRN_COLUMN_VAR_SIZE) {
    return false;
  }

  type = column->header.flags & GRN_OBJ_COLUMN_TYPE_MASK;
  return type == GRN_OBJ_COLUMN_VECTOR;
}

static inline bool
grn_column_is_index(grn_ctx *ctx, grn_obj *column)
{
  grn_obj_flags type;

  if (column->header.type == GRN_ACCESSOR) {
    grn_accessor *a;
    for (a = (grn_accessor *)column; a; a = a->next) {
      if (a->next) {
        continue;
      }
      if (a->action != GRN_ACCESSOR_GET_COLUMN_VALUE) {
        return false;
      }

      column = a->obj;
    }
  }

  if (column->header.type != GRN_COLUMN_INDEX) {
    return false;
  }

  type = column->header.flags & GRN_OBJ_COLUMN_TYPE_MASK;
  return type == GRN_OBJ_COLUMN_INDEX;
}

void
grn_obj_get_range_info(grn_ctx *ctx,
                       grn_obj *obj,
                       grn_id *range_id,
                       grn_obj_flags *range_flags)
{
  *range_flags = 0;
  if (!obj) {
    *range_id = GRN_ID_NIL;
  } else if (grn_obj_is_expr(ctx, obj)) {
    grn_expr_get_range_info(ctx, obj, range_id, range_flags);
  } else if (grn_obj_is_proc(ctx, obj)) {
    /* TODO */
    *range_id = GRN_ID_NIL;
  } else if (GRN_DB_OBJP(obj)) {
    *range_id = DB_OBJ(obj)->range;
    if (grn_column_is_vector(ctx, obj)) {
      *range_flags |= GRN_OBJ_VECTOR;
    }
    if (grn_obj_is_weight_vector_column(ctx, obj)) {
      *range_flags |= GRN_OBJ_WITH_WEIGHT;
    }
  } else if (obj->header.type == GRN_ACCESSOR) {
    bool is_vector = false;
    grn_accessor *a;
    for (a = (grn_accessor *)obj; a; a = a->next) {
      switch (a->action) {
      case GRN_ACCESSOR_GET_ID:
        *range_id = GRN_DB_UINT32;
        break;
      case GRN_ACCESSOR_GET_VALUE:
        if (GRN_DB_OBJP(a->obj)) {
          *range_id = DB_OBJ(a->obj)->range;
        }
        break;
      case GRN_ACCESSOR_GET_SCORE:
        *range_id = GRN_DB_FLOAT;
        break;
      case GRN_ACCESSOR_GET_NSUBRECS:
        *range_id = GRN_DB_INT32;
        break;
      case GRN_ACCESSOR_GET_MAX:
      case GRN_ACCESSOR_GET_MIN:
      case GRN_ACCESSOR_GET_SUM:
        *range_id = DB_OBJ(a->obj)->group.aggregated_value_type_id;
        break;
      case GRN_ACCESSOR_GET_AVG:
      case GRN_ACCESSOR_GET_MEAN:
        *range_id = GRN_DB_FLOAT;
        break;
      case GRN_ACCESSOR_GET_COLUMN_VALUE:
        grn_obj_get_range_info(ctx, a->obj, range_id, range_flags);
        if (*range_flags & GRN_OBJ_VECTOR) {
          is_vector = true;
        }
        if (is_vector) {
          *range_flags |= GRN_OBJ_VECTOR;
        }
        break;
      case GRN_ACCESSOR_GET_KEY:
        if (GRN_DB_OBJP(a->obj)) {
          *range_id = DB_OBJ(a->obj)->header.domain;
        }
        break;
      default:
        if (GRN_DB_OBJP(a->obj)) {
          *range_id = DB_OBJ(a->obj)->range;
        }
        break;
      }
    }
  }
}

grn_id
grn_obj_get_range(grn_ctx *ctx, grn_obj *obj)
{
  grn_id range_id = GRN_ID_NIL;
  grn_obj_flags range_flags = 0;

  grn_obj_get_range_info(ctx, obj, &range_id, &range_flags);

  return range_id;
}

int
grn_obj_is_persistent(grn_ctx *ctx, grn_obj *obj)
{
  int res = 0;
  if (GRN_DB_OBJP(obj)) {
    res = IS_TEMP(obj) ? 0 : 1;
  } else if (obj->header.type == GRN_ACCESSOR) {
    grn_accessor *a;
    for (a = (grn_accessor *)obj; a; a = a->next) {
      switch (a->action) {
      case GRN_ACCESSOR_GET_SCORE:
      case GRN_ACCESSOR_GET_NSUBRECS:
      case GRN_ACCESSOR_GET_MAX:
      case GRN_ACCESSOR_GET_MIN:
      case GRN_ACCESSOR_GET_SUM:
      case GRN_ACCESSOR_GET_AVG:
      case GRN_ACCESSOR_GET_MEAN:
        res = 0;
        break;
      case GRN_ACCESSOR_GET_ID:
      case GRN_ACCESSOR_GET_VALUE:
      case GRN_ACCESSOR_GET_COLUMN_VALUE:
      case GRN_ACCESSOR_GET_KEY:
        if (GRN_DB_OBJP(a->obj)) {
          res = IS_TEMP(obj) ? 0 : 1;
        }
        break;
      default:
        if (GRN_DB_OBJP(a->obj)) {
          res = IS_TEMP(obj) ? 0 : 1;
        }
        break;
      }
    }
  }
  return res;
}

const char *
grn_accessor_get_value_(grn_ctx *ctx,
                        grn_accessor *a,
                        grn_id id,
                        uint32_t *size)
{
  const char *value = NULL;
  for (;;) {
    switch (a->action) {
    case GRN_ACCESSOR_GET_ID:
      value = (const char *)(uintptr_t)id;
      *size = GRN_OBJ_GET_VALUE_IMD;
      break;
    case GRN_ACCESSOR_GET_KEY:
      value = _grn_table_key(ctx, a->obj, id, size);
      break;
    case GRN_ACCESSOR_GET_VALUE:
      value = grn_obj_get_value_(ctx, a->obj, id, size);
      break;
    case GRN_ACCESSOR_GET_SCORE:
      if ((value = grn_obj_get_value_(ctx, a->obj, id, size))) {
        value = (const char *)&((grn_rset_recinfo *)value)->score;
        *size = sizeof(double);
      }
      break;
    case GRN_ACCESSOR_GET_NSUBRECS:
      if ((value = grn_obj_get_value_(ctx, a->obj, id, size))) {
        value = (const char *)&((grn_rset_recinfo *)value)->n_subrecs;
        *size = sizeof(int);
      }
      break;
    case GRN_ACCESSOR_GET_MAX:
      if ((value = grn_obj_get_value_(ctx, a->obj, id, size))) {
        value =
          (const char *)grn_rset_recinfo_get_max_(ctx,
                                                  (grn_rset_recinfo *)value,
                                                  a->obj);
        *size = GRN_RSET_MAX_SIZE;
      }
      break;
    case GRN_ACCESSOR_GET_MIN:
      if ((value = grn_obj_get_value_(ctx, a->obj, id, size))) {
        value =
          (const char *)grn_rset_recinfo_get_min_(ctx,
                                                  (grn_rset_recinfo *)value,
                                                  a->obj);
        *size = GRN_RSET_MIN_SIZE;
      }
      break;
    case GRN_ACCESSOR_GET_SUM:
      if ((value = grn_obj_get_value_(ctx, a->obj, id, size))) {
        value =
          (const char *)grn_rset_recinfo_get_sum_(ctx,
                                                  (grn_rset_recinfo *)value,
                                                  a->obj);
        *size = GRN_RSET_SUM_SIZE;
      }
      break;
    case GRN_ACCESSOR_GET_AVG:
    case GRN_ACCESSOR_GET_MEAN:
      if ((value = grn_obj_get_value_(ctx, a->obj, id, size))) {
        value =
          (const char *)grn_rset_recinfo_get_mean_(ctx,
                                                   (grn_rset_recinfo *)value,
                                                   a->obj);
        *size = GRN_RSET_MEAN_SIZE;
      }
      break;
    case GRN_ACCESSOR_GET_COLUMN_VALUE:
      /* todo : support vector */
      value = grn_obj_get_value_(ctx, a->obj, id, size);
      break;
    case GRN_ACCESSOR_GET_DB_OBJ:
      value = _grn_table_key(ctx, ((grn_db *)ctx->impl->db)->keys, id, size);
      break;
    case GRN_ACCESSOR_LOOKUP:
      /* todo */
      break;
    case GRN_ACCESSOR_FUNCALL:
      /* todo */
      break;
    }
    if (value && (a = a->next)) {
      id = *((grn_id *)value);
    } else {
      break;
    }
  }
  return value;
}

static grn_obj *
grn_accessor_get_value(grn_ctx *ctx, grn_accessor *a, grn_id id, grn_obj *value)
{
  uint32_t vs = 0;
  uint32_t size0;
  void *vp = NULL;
  if (!value) {
    if (!(value = grn_obj_open(ctx, GRN_BULK, 0, 0))) {
      return NULL;
    }
  } else {
    value->header.type = GRN_BULK;
  }
  size0 = GRN_BULK_VSIZE(value);
  for (;;) {
    grn_bulk_truncate(ctx, value, size0);
    switch (a->action) {
    case GRN_ACCESSOR_GET_ID:
      GRN_UINT32_PUT(ctx, value, id);
      value->header.domain = GRN_DB_UINT32;
      vp = GRN_BULK_HEAD(value) + size0;
      vs = GRN_BULK_VSIZE(value) - size0;
      break;
    case GRN_ACCESSOR_GET_KEY:
      if (!a->next && GRN_TABLE_IS_MULTI_KEYS_GROUPED(a->obj)) {
        grn_obj_ensure_vector(ctx, value);
        if (id) {
          grn_obj raw_vector;
          GRN_TEXT_INIT(&raw_vector, 0);
          grn_table_get_key2(ctx, a->obj, id, &raw_vector);
          grn_vector_unpack(ctx,
                            value,
                            GRN_BULK_HEAD(&raw_vector),
                            GRN_BULK_VSIZE(&raw_vector),
                            0,
                            NULL);
          GRN_OBJ_FIN(ctx, &raw_vector);
        }
        vp = NULL;
        vs = 0;
      } else {
        if (id) {
          grn_table_get_key2(ctx, a->obj, id, value);
          vp = GRN_BULK_HEAD(value) + size0;
          vs = GRN_BULK_VSIZE(value) - size0;
        } else {
          vp = NULL;
          vs = 0;
        }
        value->header.domain = a->obj->header.domain;
      }
      break;
    case GRN_ACCESSOR_GET_VALUE:
      grn_obj_get_value(ctx, a->obj, id, value);
      vp = GRN_BULK_HEAD(value) + size0;
      vs = GRN_BULK_VSIZE(value) - size0;
      break;
    case GRN_ACCESSOR_GET_SCORE:
      {
        double score = grn_table_get_score(ctx, a->obj, id);
        GRN_FLOAT_PUT(ctx, value, score);
      }
      value->header.domain = GRN_DB_FLOAT;
      break;
    case GRN_ACCESSOR_GET_NSUBRECS:
      if (id) {
        grn_rset_recinfo *ri =
          (grn_rset_recinfo *)grn_obj_get_value_(ctx, a->obj, id, &vs);
        GRN_INT32_PUT(ctx, value, ri->n_subrecs);
      } else {
        GRN_INT32_PUT(ctx, value, 0);
      }
      value->header.domain = GRN_DB_INT32;
      break;
    case GRN_ACCESSOR_GET_MAX:
      value->header.domain = DB_OBJ(a->obj)->group.aggregated_value_type_id;
      {
        grn_rset_aggregated_value max = {0};
        if (id != GRN_ID_NIL) {
          grn_rset_recinfo *ri =
            (grn_rset_recinfo *)grn_obj_get_value_(ctx, a->obj, id, &vs);
          max = grn_rset_recinfo_get_max(ctx, ri, a->obj);
        }
        if (value->header.domain == GRN_DB_INT64) {
          GRN_INT64_PUT(ctx, value, max.value_int64);
        } else {
          GRN_FLOAT_PUT(ctx, value, max.value_double);
        }
      }
      break;
    case GRN_ACCESSOR_GET_MIN:
      value->header.domain = DB_OBJ(a->obj)->group.aggregated_value_type_id;
      {
        grn_rset_aggregated_value min = {0};
        if (id != GRN_ID_NIL) {
          grn_rset_recinfo *ri =
            (grn_rset_recinfo *)grn_obj_get_value_(ctx, a->obj, id, &vs);
          min = grn_rset_recinfo_get_min(ctx, ri, a->obj);
        }
        if (value->header.domain == GRN_DB_INT64) {
          GRN_INT64_PUT(ctx, value, min.value_int64);
        } else {
          GRN_FLOAT_PUT(ctx, value, min.value_double);
        }
      }
      break;
    case GRN_ACCESSOR_GET_SUM:
      value->header.domain = DB_OBJ(a->obj)->group.aggregated_value_type_id;
      {
        grn_rset_aggregated_value sum = {0};
        if (id != GRN_ID_NIL) {
          grn_rset_recinfo *ri =
            (grn_rset_recinfo *)grn_obj_get_value_(ctx, a->obj, id, &vs);
          sum = grn_rset_recinfo_get_sum(ctx, ri, a->obj);
        }
        if (value->header.domain == GRN_DB_INT64) {
          GRN_INT64_PUT(ctx, value, sum.value_int64);
        } else {
          GRN_FLOAT_PUT(ctx, value, sum.value_double);
        }
      }
      break;
    case GRN_ACCESSOR_GET_AVG:
    case GRN_ACCESSOR_GET_MEAN:
      if (id) {
        grn_rset_recinfo *ri =
          (grn_rset_recinfo *)grn_obj_get_value_(ctx, a->obj, id, &vs);
        double mean;
        mean = grn_rset_recinfo_get_mean(ctx, ri, a->obj);
        GRN_FLOAT_PUT(ctx, value, mean);
      } else {
        GRN_FLOAT_PUT(ctx, value, 0.0);
      }
      value->header.domain = GRN_DB_FLOAT;
      break;
    case GRN_ACCESSOR_GET_COLUMN_VALUE:
      if (grn_obj_is_index_column(ctx, a->obj) && a->next) {
        grn_id sub_value_range = grn_obj_get_range(ctx, (grn_obj *)(a->next));
        grn_obj_reinit(ctx, value, sub_value_range, GRN_OBJ_VECTOR);
        grn_obj sub_value;
        GRN_VOID_INIT(&sub_value);
        grn_ii *ii = (grn_ii *)(a->obj);
        grn_ii_cursor *cursor =
          grn_ii_cursor_open(ctx,
                             ii,
                             id,
                             GRN_ID_NIL,
                             GRN_ID_MAX,
                             grn_ii_get_n_elements(ctx, ii),
                             0);
        if (cursor) {
          grn_posting *posting;
          while ((posting = grn_ii_cursor_next(ctx, cursor))) {
            GRN_BULK_REWIND(&sub_value);
            grn_accessor_get_value(ctx, a->next, posting->rid, &sub_value);
            if (value->header.type == GRN_UVECTOR) {
              grn_bulk_write(ctx,
                             value,
                             GRN_BULK_HEAD(&sub_value),
                             GRN_BULK_VSIZE(&sub_value));
            } else {
              grn_vector_add_element(ctx,
                                     value,
                                     GRN_BULK_HEAD(&sub_value),
                                     GRN_BULK_VSIZE(&sub_value),
                                     0,
                                     sub_value.header.domain);
            }
          }
          grn_ii_cursor_close(ctx, cursor);
        }
        GRN_OBJ_FIN(ctx, &sub_value);
        return value;
      } else {
        grn_obj_get_value(ctx, a->obj, id, value);
        if (value->header.type == GRN_UVECTOR && a->next) {
          int i, n;
          grn_id *sub_ids;
          grn_obj sub_records;
          grn_obj sub_value;
          grn_id sub_value_range;

          n = (GRN_BULK_VSIZE(value) - size0) / sizeof(grn_id);
          sub_ids = (grn_id *)(GRN_BULK_HEAD(value) + size0);
          GRN_RECORD_INIT(&sub_records, GRN_OBJ_VECTOR, value->header.domain);
          for (i = 0; i < n; i++) {
            GRN_RECORD_PUT(ctx, &sub_records, sub_ids[i]);
          }

          sub_value_range = grn_obj_get_range(ctx, (grn_obj *)(a->next));
          grn_obj_reinit(ctx, value, sub_value_range, GRN_OBJ_VECTOR);
          GRN_VOID_INIT(&sub_value);
          for (i = 0; i < n; i++) {
            grn_id sub_id = GRN_RECORD_VALUE_AT(&sub_records, i);
            GRN_BULK_REWIND(&sub_value);
            grn_accessor_get_value(ctx, a->next, sub_id, &sub_value);
            if (value->header.type == GRN_UVECTOR) {
              grn_bulk_write(ctx,
                             value,
                             GRN_BULK_HEAD(&sub_value),
                             GRN_BULK_VSIZE(&sub_value));
            } else {
              grn_vector_add_element(ctx,
                                     value,
                                     GRN_BULK_HEAD(&sub_value),
                                     GRN_BULK_VSIZE(&sub_value),
                                     0,
                                     sub_value.header.domain);
            }
          }
          GRN_OBJ_FIN(ctx, &sub_value);
          GRN_OBJ_FIN(ctx, &sub_records);
          return value;
        } else {
          vp = GRN_BULK_HEAD(value) + size0;
          vs = GRN_BULK_VSIZE(value) - size0;
        }
      }
      break;
    case GRN_ACCESSOR_GET_DB_OBJ:
      value = grn_ctx_at(ctx, id);
      grn_obj_close(ctx, value);
      return value;
      break;
    case GRN_ACCESSOR_LOOKUP:
      /* todo */
      break;
    case GRN_ACCESSOR_FUNCALL:
      /* todo */
      break;
    }
    if ((a = a->next)) {
      if (vs > 0) {
        id = *((grn_id *)vp);
      } else {
        id = GRN_ID_NIL;
      }
    } else {
      break;
    }
  }
  return value;
}

static grn_rset_aggregated_value
grn_accessor_set_value_get_rset_aggregated_value(grn_ctx *ctx,
                                                 grn_obj *table,
                                                 grn_obj *value)
{
  grn_rset_aggregated_value aggregated_value = {0};
  grn_id type_id = DB_OBJ(table)->group.aggregated_value_type_id;
  if (type_id == GRN_DB_INT64) {
    if (value->header.type == GRN_DB_INT64) {
      aggregated_value.value_int64 = GRN_INT64_VALUE(value);
    } else {
      grn_obj value_int64;
      GRN_INT64_INIT(&value_int64, 0);
      if (grn_obj_cast(ctx, value, &value_int64, false) == GRN_SUCCESS) {
        aggregated_value.value_int64 = GRN_INT64_VALUE(&value_int64);
      }
      GRN_OBJ_FIN(ctx, &value_int64);
    }
  } else {
    if (value->header.type == GRN_DB_FLOAT) {
      aggregated_value.value_double = GRN_FLOAT_VALUE(value);
    } else {
      grn_obj value_float;
      GRN_FLOAT_INIT(&value_float, 0);
      if (grn_obj_cast(ctx, value, &value_float, false) == GRN_SUCCESS) {
        aggregated_value.value_double = GRN_FLOAT_VALUE(&value_float);
      }
      GRN_OBJ_FIN(ctx, &value_float);
    }
  }
  return aggregated_value;
}

static grn_rc
grn_accessor_set_value(
  grn_ctx *ctx, grn_accessor *a, grn_id id, grn_obj *value, int flags)
{
  grn_rc rc = GRN_SUCCESS;
  if (!value) {
    value = grn_obj_open(ctx, GRN_BULK, 0, 0);
  }
  if (value) {
    grn_obj buf;
    void *vp = NULL;
    GRN_TEXT_INIT(&buf, 0);
    for (;;) {
      GRN_BULK_REWIND(&buf);
      switch (a->action) {
      case GRN_ACCESSOR_GET_KEY:
        grn_table_get_key2(ctx, a->obj, id, &buf);
        vp = GRN_BULK_HEAD(&buf);
        break;
      case GRN_ACCESSOR_GET_VALUE:
        if (a->next) {
          grn_obj_get_value(ctx, a->obj, id, &buf);
          vp = GRN_BULK_HEAD(&buf);
        } else {
          rc = grn_obj_set_value(ctx, a->obj, id, value, flags);
        }
        break;
      case GRN_ACCESSOR_GET_SCORE:
        {
          grn_rset_recinfo *ri;
          if (a->next) {
            grn_obj_get_value(ctx, a->obj, id, &buf);
            ri = (grn_rset_recinfo *)GRN_BULK_HEAD(&buf);
            vp = &ri->score;
          } else {
            uint32_t size;
            if ((ri = (grn_rset_recinfo *)
                   grn_obj_get_value_(ctx, a->obj, id, &size))) {
              // todo : flags support
              if (value->header.domain == GRN_DB_FLOAT) {
                ri->score = GRN_FLOAT_VALUE(value);
              } else {
                grn_obj buf;
                GRN_FLOAT_INIT(&buf, 0);
                grn_obj_cast(ctx, value, &buf, GRN_FALSE);
                ri->score = GRN_FLOAT_VALUE(&buf);
                GRN_OBJ_FIN(ctx, &buf);
              }
            }
          }
        }
        break;
      case GRN_ACCESSOR_GET_NSUBRECS:
        grn_obj_get_value(ctx, a->obj, id, &buf);
        {
          grn_rset_recinfo *ri = (grn_rset_recinfo *)GRN_BULK_HEAD(&buf);
          vp = &ri->n_subrecs;
        }
        break;
      case GRN_ACCESSOR_GET_MAX:
        grn_obj_get_value(ctx, a->obj, id, &buf);
        {
          grn_rset_recinfo *ri = (grn_rset_recinfo *)GRN_BULK_HEAD(&buf);
          grn_rset_aggregated_value max =
            grn_accessor_set_value_get_rset_aggregated_value(ctx,
                                                             a->obj,
                                                             value);
          grn_rset_recinfo_set_max(ctx, ri, a->obj, max);
        }
        break;
      case GRN_ACCESSOR_GET_MIN:
        grn_obj_get_value(ctx, a->obj, id, &buf);
        {
          grn_rset_recinfo *ri = (grn_rset_recinfo *)GRN_BULK_HEAD(&buf);
          grn_rset_aggregated_value min =
            grn_accessor_set_value_get_rset_aggregated_value(ctx,
                                                             a->obj,
                                                             value);
          grn_rset_recinfo_set_min(ctx, ri, a->obj, min);
        }
        break;
      case GRN_ACCESSOR_GET_SUM:
        grn_obj_get_value(ctx, a->obj, id, &buf);
        {
          grn_rset_recinfo *ri = (grn_rset_recinfo *)GRN_BULK_HEAD(&buf);
          grn_rset_aggregated_value sum =
            grn_accessor_set_value_get_rset_aggregated_value(ctx,
                                                             a->obj,
                                                             value);
          grn_rset_recinfo_set_sum(ctx, ri, a->obj, sum);
        }
        break;
      case GRN_ACCESSOR_GET_AVG:
      case GRN_ACCESSOR_GET_MEAN:
        grn_obj_get_value(ctx, a->obj, id, &buf);
        {
          grn_rset_recinfo *ri = (grn_rset_recinfo *)GRN_BULK_HEAD(&buf);
          if (value->header.type == GRN_DB_FLOAT) {
            grn_rset_recinfo_set_mean(ctx, ri, a->obj, GRN_FLOAT_VALUE(value));
          } else {
            grn_obj value_float;
            GRN_FLOAT_INIT(&value_float, 0);
            if (!grn_obj_cast(ctx, value, &value_float, GRN_FALSE)) {
              grn_rset_recinfo_set_mean(ctx,
                                        ri,
                                        a->obj,
                                        GRN_FLOAT_VALUE(&value_float));
            }
            GRN_OBJ_FIN(ctx, &value_float);
          }
        }
        break;
      case GRN_ACCESSOR_GET_COLUMN_VALUE:
        /* todo : support vector */
        if (a->next) {
          grn_obj_get_value(ctx, a->obj, id, &buf);
          vp = GRN_BULK_HEAD(&buf);
        } else {
          rc = grn_obj_set_value(ctx, a->obj, id, value, flags);
        }
        break;
      case GRN_ACCESSOR_LOOKUP:
        /* todo */
        break;
      case GRN_ACCESSOR_FUNCALL:
        /* todo */
        break;
      }
      if ((a = a->next)) {
        id = *((grn_id *)vp);
      } else {
        break;
      }
    }
    grn_obj_close(ctx, &buf);
  }
  return rc;
}

uint32_t
grn_obj_size(grn_ctx *ctx, grn_obj *obj)
{
  if (!obj) {
    return 0;
  }
  switch (obj->header.type) {
  case GRN_VOID:
  case GRN_BULK:
  case GRN_PTR:
  case GRN_UVECTOR:
  case GRN_PVECTOR:
  case GRN_MSG:
    return GRN_BULK_VSIZE(obj);
  case GRN_VECTOR:
    return obj->u.v.body ? GRN_BULK_VSIZE(obj->u.v.body) : 0;
  default:
    return 0;
  }
}

static inline bool
is_same_value(grn_ctx *ctx, grn_obj *value1, grn_obj *value2)
{
  void *v1 = GRN_BULK_HEAD(value1);
  uint32_t size1 = grn_obj_size(ctx, value1);
  void *v2 = GRN_BULK_HEAD(value2);
  uint32_t size2 = grn_obj_size(ctx, value2);
  if (size1 != size2) {
    return false;
  }
  if (memcmp(v1, v2, size1) != 0) {
    return false;
  }
  uint32_t n_elements1 = 0;
  if (value1 && value1->header.type == GRN_VECTOR) {
    n_elements1 = grn_vector_size(ctx, value1);
  }
  uint32_t n_elements2 = 0;
  if (value2 && value2->header.type == GRN_VECTOR) {
    n_elements2 = grn_vector_size(ctx, value2);
  }
  if (n_elements1 != n_elements2) {
    return false;
  }
  return true;
}

static inline bool
call_hook(grn_ctx *ctx, grn_obj *obj, grn_id id, grn_obj *value, int flags)
{
  grn_hook *hooks = DB_OBJ(obj)->hooks[GRN_HOOK_SET];
  if (hooks || obj->header.type == GRN_COLUMN_VAR_SIZE) {
    grn_obj oldbuf, *oldvalue;
    GRN_TEXT_INIT(&oldbuf, 0);
    oldvalue = grn_obj_get_value(ctx, obj, id, &oldbuf);
    if (flags & GRN_OBJ_SET) {
      bool need_update = true;
      if (is_same_value(ctx, value, oldvalue)) {
        if (obj->header.type == GRN_COLUMN_FIX_SIZE) {
          /* We don't need to update the same value but fixed zero
           * value must be updated because we can't distinct no value
           * and zero value. For example, grn_obj_get_value() for
           * Int32 scalar column returns 0 as the initial value. */
          need_update = grn_bulk_is_zero(ctx, value);
        } else {
          /* We don't need to update the same value. */
          need_update = false;
        }
      }
      if (!need_update) {
        grn_obj_close(ctx, oldvalue);
        return false;
      }
    }
    if (hooks) {
      // todo : grn_proc_ctx_open()
      grn_obj id_, flags_;
      grn_proc_ctx pctx;
      grn_proc_ctx_init(&pctx, hooks, 4, 4);
      GRN_UINT32_INIT(&id_, 0);
      GRN_UINT32_INIT(&flags_, 0);
      GRN_UINT32_SET(ctx, &id_, id);
      GRN_UINT32_SET(ctx, &flags_, flags);
      while (hooks) {
        grn_ctx_push(ctx, &id_);
        grn_ctx_push(ctx, oldvalue);
        grn_ctx_push(ctx, value);
        grn_ctx_push(ctx, &flags_);
        pctx.caller = NULL;
        pctx.currh = hooks;
        if (hooks->proc) {
          hooks->proc->funcs[PROC_INIT](ctx, 1, &obj, &pctx.user_data);
        } else {
          grn_obj_default_set_value_hook(ctx, 1, &obj, &pctx.user_data);
        }
        if (ctx->rc) {
          grn_obj_close(ctx, oldvalue);
          return false;
        }
        hooks = hooks->next;
        pctx.offset++;
      }
      GRN_OBJ_FIN(ctx, &id_);
      GRN_OBJ_FIN(ctx, &flags_);
    }
    grn_obj_close(ctx, oldvalue);
  }
  return true;
}

static grn_rc
grn_obj_set_value_table_pat_key(
  grn_ctx *ctx, grn_obj *obj, grn_id id, grn_obj *value, int flags)
{
  grn_rc rc = GRN_INVALID_ARGUMENT;
  grn_id range = DB_OBJ(obj)->range;
  void *v = GRN_BULK_HEAD(value);
  grn_obj buf;

  if (!call_hook(ctx, obj, id, value, flags)) {
    if (ctx->rc) {
      rc = ctx->rc;
    }
    return rc;
  }

  if (range != value->header.domain) {
    GRN_OBJ_INIT(&buf, GRN_BULK, 0, range);
    if (grn_obj_cast(ctx, value, &buf, GRN_TRUE) == GRN_SUCCESS) {
      v = GRN_BULK_HEAD(&buf);
    }
  }
  rc = grn_pat_set_value(ctx, (grn_pat *)obj, id, v, flags);
  if (range != value->header.domain) {
    grn_obj_close(ctx, &buf);
  }

  return rc;
}

static grn_rc
grn_obj_set_value_table_hash_key(
  grn_ctx *ctx, grn_obj *obj, grn_id id, grn_obj *value, int flags)
{
  grn_rc rc = GRN_INVALID_ARGUMENT;
  grn_id range = DB_OBJ(obj)->range;
  void *v = GRN_BULK_HEAD(value);
  grn_obj buf;

  if (!call_hook(ctx, obj, id, value, flags)) {
    if (ctx->rc) {
      rc = ctx->rc;
    }
    return rc;
  }

  if (range != value->header.domain) {
    GRN_OBJ_INIT(&buf, GRN_BULK, 0, range);
    if (grn_obj_cast(ctx, value, &buf, GRN_TRUE) == GRN_SUCCESS) {
      v = GRN_BULK_HEAD(&buf);
    }
  }
  rc = grn_hash_set_value(ctx, (grn_hash *)obj, id, v, flags);
  if (range != value->header.domain) {
    grn_obj_close(ctx, &buf);
  }

  return rc;
}

static grn_rc
grn_obj_set_value_table_no_key(
  grn_ctx *ctx, grn_obj *obj, grn_id id, grn_obj *value, int flags)
{
  grn_rc rc = GRN_INVALID_ARGUMENT;
  grn_id range = DB_OBJ(obj)->range;
  void *v = GRN_BULK_HEAD(value);
  grn_obj buf;

  if (!call_hook(ctx, obj, id, value, flags)) {
    if (ctx->rc) {
      rc = ctx->rc;
    }
    return rc;
  }

  if (range != value->header.domain) {
    GRN_OBJ_INIT(&buf, GRN_BULK, 0, range);
    if (grn_obj_cast(ctx, value, &buf, GRN_TRUE) == GRN_SUCCESS) {
      v = GRN_BULK_HEAD(&buf);
    }
  }
  rc = grn_array_set_value(ctx, (grn_array *)obj, id, v, flags);
  if (range != value->header.domain) {
    grn_obj_close(ctx, &buf);
  }

  return rc;
}

static grn_rc
grn_obj_set_value_column_var_size(
  grn_ctx *ctx, grn_obj *column, grn_id id, grn_obj *value, int flags)
{
  grn_ja *ja = (grn_ja *)column;
  grn_obj buffer;
  GRN_VOID_INIT(&buffer);
  grn_obj *casted_value = grn_ja_cast_value(ctx, ja, value, &buffer, flags);
  grn_rc rc = ctx->rc;
  if (casted_value) {
    if (call_hook(ctx, column, id, casted_value, flags)) {
      switch (casted_value->header.type) {
      case GRN_VOID:
        rc = grn_ja_put(ctx, ja, id, NULL, 0, flags, NULL);
        break;
      case GRN_VECTOR:
        rc = grn_ja_putv(ctx, ja, id, casted_value, flags);
        break;
      default:
        {
          grn_rc pack_rc = GRN_SUCCESS;
          if (casted_value == &buffer) {
            pack_rc = grn_ja_pack_value(ctx, ja, casted_value, flags);
          }
          if (pack_rc == GRN_SUCCESS) {
            rc = grn_ja_put(ctx,
                            ja,
                            id,
                            GRN_BULK_HEAD(casted_value),
                            GRN_BULK_VSIZE(casted_value),
                            flags,
                            NULL);
          } else {
            rc = pack_rc;
          }
        }
        break;
      }
    } else {
      if (ctx->rc != GRN_SUCCESS) {
        rc = ctx->rc;
      }
    }
  }
  GRN_OBJ_FIN(ctx, &buffer);
  return rc;
}

static grn_rc
grn_obj_set_value_column_fix_size(
  grn_ctx *ctx, grn_obj *obj, grn_id id, grn_obj *value, int flags)
{
  grn_rc rc = GRN_SUCCESS;
  grn_obj buffer;
  GRN_VOID_INIT(&buffer);
  grn_obj *value_ =
    grn_ra_cast_value(ctx, (grn_ra *)obj, value, &buffer, flags);
  if (!value_) {
    goto exit;
  }
  uint32_t value_size = GRN_BULK_VSIZE(value_);
  uint32_t element_size = ((grn_ra *)obj)->header->element_size;
  if (value_size > element_size) {
    GRN_DEFINE_NAME(obj);
    ERR(GRN_INVALID_ARGUMENT,
        "[column][fix][set-value][%.*s] too long value: <%u>: max:<%u>",
        name_size,
        name,
        value_size,
        element_size);
    goto exit;
  }
  switch (flags & GRN_OBJ_SET_MASK) {
  case GRN_OBJ_SET:
  case GRN_OBJ_INCR:
  case GRN_OBJ_DECR:
    if (!call_hook(ctx, obj, id, value_, flags)) {
      if (ctx->rc != GRN_SUCCESS) {
        rc = ctx->rc;
        goto exit;
      }
    }
    rc = grn_ra_set_value(ctx, (grn_ra *)obj, id, value_, flags);
    break;
  default:
    rc = GRN_OPERATION_NOT_SUPPORTED;
    {
      GRN_DEFINE_NAME(obj);
      ERR(rc,
          "[column][fix][set-value][%.*s] unsupported set mode: <%s>(%u)",
          name_size,
          name,
          grn_obj_set_flag_to_string(flags),
          flags & GRN_OBJ_SET_MASK);
    }
    break;
  }
exit:
  GRN_OBJ_FIN(ctx, &buffer);
  return rc;
}

static grn_rc
grn_obj_set_value_column_index(
  grn_ctx *ctx, grn_obj *obj, grn_id id, grn_obj *value, int flags)
{
  char column_name[GRN_TABLE_MAX_KEY_SIZE];
  int column_name_size;
  column_name_size =
    grn_obj_name(ctx, obj, column_name, GRN_TABLE_MAX_KEY_SIZE);
  ERR(GRN_INVALID_ARGUMENT,
      "can't set value to index column directly: <%.*s>",
      column_name_size,
      column_name);
  return ctx->rc;
}

grn_rc
grn_obj_set_value(
  grn_ctx *ctx, grn_obj *obj, grn_id id, grn_obj *value, int flags)
{
  grn_rc rc = GRN_INVALID_ARGUMENT;
  GRN_API_ENTER;
  if (!GRN_DB_OBJP(obj)) {
    if (obj->header.type == GRN_ACCESSOR) {
      rc = grn_accessor_set_value(ctx, (grn_accessor *)obj, id, value, flags);
    } else {
      ERR(GRN_INVALID_ARGUMENT, "not db_obj");
    }
  } else {
    GRN_SLOW_LOG_PUSH(ctx, GRN_LOG_DEBUG);
    switch (obj->header.type) {
    case GRN_TABLE_PAT_KEY:
      rc = grn_obj_set_value_table_pat_key(ctx, obj, id, value, flags);
      break;
    case GRN_TABLE_DAT_KEY:
      rc = GRN_OPERATION_NOT_SUPPORTED;
      break;
    case GRN_TABLE_HASH_KEY:
      rc = grn_obj_set_value_table_hash_key(ctx, obj, id, value, flags);
      break;
    case GRN_TABLE_NO_KEY:
      rc = grn_obj_set_value_table_no_key(ctx, obj, id, value, flags);
      break;
    case GRN_COLUMN_VAR_SIZE:
      rc = grn_obj_set_value_column_var_size(ctx, obj, id, value, flags);
      break;
    case GRN_COLUMN_FIX_SIZE:
      rc = grn_obj_set_value_column_fix_size(ctx, obj, id, value, flags);
      break;
    case GRN_COLUMN_INDEX:
      rc = grn_obj_set_value_column_index(ctx, obj, id, value, flags);
      break;
    default:
      break;
    }
    GRN_SLOW_LOG_POP_BEGIN(ctx, GRN_LOG_DEBUG, elapsed_time)
    {
      GRN_DEFINE_NAME(obj);
      GRN_LOG(ctx,
              GRN_LOG_DEBUG,
              "[obj][set-value][slow][%f] "
              "<%.*s>(%u)",
              elapsed_time,
              name_size,
              name,
              id);
    }
    GRN_SLOW_LOG_POP_END(ctx);
  }
  GRN_API_RETURN(rc);
}

const char *
grn_obj_get_value_(grn_ctx *ctx, grn_obj *obj, grn_id id, uint32_t *size)
{
  const char *value = NULL;
  *size = 0;
  switch (obj->header.type) {
  case GRN_ACCESSOR:
    value = grn_accessor_get_value_(ctx, (grn_accessor *)obj, id, size);
    break;
  case GRN_TABLE_PAT_KEY:
    value = grn_pat_get_value_(ctx, (grn_pat *)obj, id, size);
    break;
  case GRN_TABLE_DAT_KEY:
    ERR(GRN_FUNCTION_NOT_IMPLEMENTED, "GRN_TABLE_DAT_KEY not supported");
    break;
  case GRN_TABLE_HASH_KEY:
    value = grn_hash_get_value_(ctx, (grn_hash *)obj, id, size);
    break;
  case GRN_TABLE_NO_KEY:
    if ((value = _grn_array_get_value(ctx, (grn_array *)obj, id))) {
      *size = ((grn_array *)obj)->value_size;
    }
    break;
  case GRN_COLUMN_VAR_SIZE:
    {
      grn_io_win jw;
      if ((value = grn_ja_ref(ctx, (grn_ja *)obj, id, &jw, size))) {
        grn_ja_unref(ctx, &jw);
      }
    }
    break;
  case GRN_COLUMN_FIX_SIZE:
    if ((value = grn_ra_ref(ctx, (grn_ra *)obj, id))) {
      grn_ra_unref(ctx, (grn_ra *)obj, id);
      *size = ((grn_ra *)obj)->header->element_size;
    }
    break;
  case GRN_COLUMN_INDEX:
    ERR(GRN_FUNCTION_NOT_IMPLEMENTED, "todo: GRN_COLUMN_INDEX");
    break;
  }
  return value;
}

static void
grn_obj_get_value_expr(grn_ctx *ctx, grn_obj *expr, grn_id id, grn_obj *value)
{
  grn_expr *e = (grn_expr *)expr;
  grn_expr_code *code;

  if (e->codes_curr != 1) {
    return;
  }

  code = e->codes;
  if (code->op != GRN_OP_GET_VALUE) {
    return;
  }

  if (!code->value) {
    return;
  }

  switch (code->value->header.type) {
  case GRN_ACCESSOR:
  case GRN_COLUMN_VAR_SIZE:
  case GRN_COLUMN_FIX_SIZE:
    grn_obj_get_value(ctx, code->value, id, value);
    break;
  default:
    break;
  }
}

static void
grn_obj_get_value_column_index(grn_ctx *ctx,
                               grn_obj *index_column,
                               grn_id id,
                               grn_obj *value)
{
  grn_ii *ii = (grn_ii *)index_column;
  grn_obj_ensure_bulk(ctx, value);
  if (id) {
    GRN_UINT32_SET(ctx, value, grn_ii_estimate_size(ctx, ii, id));
  } else {
    GRN_UINT32_SET(ctx, value, 0);
  }
  value->header.domain = GRN_DB_UINT32;
}

static grn_obj *
grn_obj_get_value_column_vector(grn_ctx *ctx,
                                grn_obj *obj,
                                grn_id id,
                                grn_obj *value)
{
  bool is_var_size_element =
    grn_type_id_is_text_family(ctx, DB_OBJ(obj)->range);
  if (is_var_size_element) {
    grn_obj_ensure_vector(ctx, value);
    value->header.domain = DB_OBJ(obj)->range;
    if (id) {
      grn_ja_get_value(ctx, (grn_ja *)obj, id, value);
    }
  } else {
    grn_obj_ensure_bulk(ctx, value);
    value->header.type = GRN_UVECTOR;
    value->header.domain = DB_OBJ(obj)->range;
    grn_column_flags flags = grn_column_get_flags(ctx, obj);
    if (flags & GRN_OBJ_WITH_WEIGHT) {
      value->header.flags |= GRN_OBJ_WITH_WEIGHT;
    }
    if (id) {
      grn_ja_get_value(ctx, (grn_ja *)obj, id, value);
    }
  }

  return value;
}

grn_obj *
grn_obj_get_value(grn_ctx *ctx, grn_obj *obj, grn_id id, grn_obj *value)
{
  GRN_API_ENTER;
  if (!obj) {
    ERR(GRN_INVALID_ARGUMENT, "grn_obj_get_value failed");
    goto exit;
  }
  if (!value) {
    if (!(value = grn_obj_open(ctx, GRN_BULK, 0, 0))) {
      ERR(GRN_INVALID_ARGUMENT, "grn_obj_get_value failed");
      goto exit;
    }
  }
  switch (value->header.type) {
  case GRN_VOID:
    grn_obj_reinit(ctx, value, GRN_DB_TEXT, 0);
    break;
  case GRN_BULK:
  case GRN_VECTOR:
  case GRN_UVECTOR:
  case GRN_MSG:
    break;
  default:
    ERR(GRN_INVALID_ARGUMENT, "grn_obj_get_value failed");
    goto exit;
  }
  switch (obj->header.type) {
  case GRN_ACCESSOR:
    grn_obj_ensure_bulk(ctx, value);
    value = grn_accessor_get_value(ctx, (grn_accessor *)obj, id, value);
    break;
  case GRN_EXPR:
    grn_obj_get_value_expr(ctx, obj, id, value);
    break;
  case GRN_TABLE_PAT_KEY:
    {
      grn_pat *pat = (grn_pat *)obj;
      uint32_t size = pat->value_size;
      grn_obj_ensure_bulk(ctx, value);
      if (id) {
        if (grn_bulk_space(ctx, value, size)) {
          MERR("grn_bulk_space failed");
          goto exit;
        }
        {
          char *curr = GRN_BULK_CURR(value);
          grn_pat_get_value(ctx, pat, id, curr - size);
        }
      }
      value->header.type = GRN_BULK;
      value->header.domain = grn_obj_get_range(ctx, obj);
    }
    break;
  case GRN_TABLE_DAT_KEY:
    ERR(GRN_FUNCTION_NOT_IMPLEMENTED, "GRN_TABLE_DAT_KEY not supported");
    break;
  case GRN_TABLE_HASH_KEY:
    {
      grn_bool processed = GRN_FALSE;
      grn_obj_ensure_bulk(ctx, value);
      value->header.domain = grn_obj_get_range(ctx, obj);
      if (id) {
        if (GRN_TABLE_IS_MULTI_KEYS_GROUPED(obj)) {
          grn_obj *domain;
          domain = grn_ctx_at(ctx, value->header.domain);
          if (GRN_OBJ_TABLEP(domain)) {
            grn_id subrec_id;
            if (grn_table_get_subrecs(ctx, obj, id, &subrec_id, NULL, 1) == 1) {
              GRN_RECORD_PUT(ctx, value, subrec_id);
              processed = GRN_TRUE;
            }
          }
          grn_obj_unref(ctx, domain);
        }
        if (!processed) {
          grn_hash *hash = (grn_hash *)obj;
          uint32_t size = hash->value_size;
          if (grn_bulk_space(ctx, value, size)) {
            MERR("grn_bulk_space failed");
            goto exit;
          }
          {
            char *curr = GRN_BULK_CURR(value);
            grn_hash_get_value(ctx, hash, id, curr - size);
          }
        }
      }
    }
    break;
  case GRN_TABLE_NO_KEY:
    {
      grn_array *array = (grn_array *)obj;
      uint32_t size = array->value_size;
      grn_obj_ensure_bulk(ctx, value);
      if (id) {
        if (grn_bulk_space(ctx, value, size)) {
          MERR("grn_bulk_space failed");
          goto exit;
        }
        {
          char *curr = GRN_BULK_CURR(value);
          grn_array_get_value(ctx, array, id, curr - size);
        }
      }
      value->header.type = GRN_BULK;
      value->header.domain = grn_obj_get_range(ctx, obj);
    }
    break;
  case GRN_COLUMN_VAR_SIZE:
    switch (obj->header.flags & GRN_OBJ_COLUMN_TYPE_MASK) {
    case GRN_OBJ_COLUMN_VECTOR:
      grn_obj_get_value_column_vector(ctx, obj, id, value);
      break;
    case GRN_OBJ_COLUMN_SCALAR:
      grn_obj_ensure_bulk(ctx, value);
      if (id) {
        grn_ja_get_value(ctx, (grn_ja *)obj, id, value);
      }
      value->header.type = GRN_BULK;
      break;
    default:
      ERR(GRN_FILE_CORRUPT, "invalid GRN_OBJ_COLUMN_TYPE");
      break;
    }
    value->header.domain = grn_obj_get_range(ctx, obj);
    break;
  case GRN_COLUMN_FIX_SIZE:
    grn_obj_ensure_bulk(ctx, value);
    value->header.type = GRN_BULK;
    value->header.domain = grn_obj_get_range(ctx, obj);
    if (id) {
      unsigned int element_size;
      void *v = grn_ra_ref(ctx, (grn_ra *)obj, id);
      if (v) {
        element_size = ((grn_ra *)obj)->header->element_size;
        grn_bulk_write(ctx, value, v, element_size);
        grn_ra_unref(ctx, (grn_ra *)obj, id);
      }
    }
    break;
  case GRN_COLUMN_INDEX:
    grn_obj_get_value_column_index(ctx, obj, id, value);
    break;
  }
exit:
  GRN_API_RETURN(value);
}

int
grn_obj_get_values(grn_ctx *ctx, grn_obj *obj, grn_id offset, void **values)
{
  int nrecords = -1;
  GRN_API_ENTER;
  if (obj->header.type == GRN_COLUMN_FIX_SIZE) {
    grn_obj *domain = grn_column_table(ctx, obj);
    if (domain) {
      unsigned int table_size = grn_table_size(ctx, domain);
      if (0 < offset && offset <= table_size) {
        grn_ra *ra = (grn_ra *)obj;
        void *p = grn_ra_ref(ctx, ra, offset);
        if (p) {
          if ((offset >> ra->element_width) ==
              (table_size >> ra->element_width)) {
            nrecords =
              (table_size & ra->element_mask) + 1 - (offset & ra->element_mask);
          } else {
            nrecords = ra->element_mask + 1 - (offset & ra->element_mask);
          }
          if (values) {
            *values = p;
          }
          grn_ra_unref(ctx, ra, offset);
        } else {
          ERR(GRN_NO_MEMORY_AVAILABLE, "ra get failed");
        }
      } else {
        nrecords = 0;
      }
    } else {
      ERR(GRN_INVALID_ARGUMENT, "no domain found");
    }
  } else {
    ERR(GRN_INVALID_ARGUMENT, "obj is not a fix sized column");
  }
  GRN_API_RETURN(nrecords);
}

grn_rc
grn_column_index_update(grn_ctx *ctx,
                        grn_obj *column,
                        grn_id id,
                        unsigned int section,
                        grn_obj *oldvalue,
                        grn_obj *newvalue)
{
  grn_rc rc = GRN_INVALID_ARGUMENT;
  GRN_API_ENTER;
  if (column->header.type != GRN_COLUMN_INDEX) {
    ERR(GRN_INVALID_ARGUMENT, "invalid column assigned");
  } else {
    rc = grn_ii_column_update(ctx,
                              (grn_ii *)column,
                              id,
                              section,
                              oldvalue,
                              newvalue,
                              NULL);
  }
  GRN_API_RETURN(rc);
}

grn_obj *
grn_column_table(grn_ctx *ctx, grn_obj *column)
{
  grn_obj *obj = NULL;
  grn_db_obj *col = DB_OBJ(column);
  GRN_API_ENTER;
  if (col) {
    obj = grn_ctx_at(ctx, col->header.domain);
  }
  GRN_API_RETURN(obj);
}

grn_obj *
grn_obj_get_info(grn_ctx *ctx,
                 grn_obj *obj,
                 grn_info_type type,
                 grn_obj *valuebuf)
{
  const char *tag = "[obj][get-info]";
  GRN_API_ENTER;
  switch (type) {
  case GRN_INFO_SUPPORT_ZLIB:
    if (!valuebuf &&
        !(valuebuf = grn_obj_open(ctx, GRN_BULK, 0, GRN_DB_BOOL))) {
      ERR(GRN_INVALID_ARGUMENT,
          "%s[support-zlib] failed to allocate value buffer",
          tag);
      goto exit;
    }
#ifdef GRN_WITH_ZLIB
    GRN_BOOL_PUT(ctx, valuebuf, GRN_TRUE);
#else
    GRN_BOOL_PUT(ctx, valuebuf, GRN_FALSE);
#endif
    break;
  case GRN_INFO_SUPPORT_LZ4:
    if (!valuebuf &&
        !(valuebuf = grn_obj_open(ctx, GRN_BULK, 0, GRN_DB_BOOL))) {
      ERR(GRN_INVALID_ARGUMENT,
          "%s[support-lz4] failed to allocate value buffer",
          tag);
      goto exit;
    }
#ifdef GRN_WITH_LZ4
    GRN_BOOL_PUT(ctx, valuebuf, GRN_TRUE);
#else  /* GRN_WITH_LZ4 */
    GRN_BOOL_PUT(ctx, valuebuf, GRN_FALSE);
#endif /* GRN_WITH_LZ4 */
    break;
  case GRN_INFO_SUPPORT_ZSTD:
    if (!valuebuf &&
        !(valuebuf = grn_obj_open(ctx, GRN_BULK, 0, GRN_DB_BOOL))) {
      ERR(GRN_INVALID_ARGUMENT,
          "%s[support-zstd] failed to allocate value buffer",
          tag);
      goto exit;
    }
#ifdef GRN_WITH_ZSTD
    GRN_BOOL_PUT(ctx, valuebuf, GRN_TRUE);
#else  /* GRN_WITH_ZSTD */
    GRN_BOOL_PUT(ctx, valuebuf, GRN_FALSE);
#endif /* GRN_WITH_ZSTD */
    break;
  case GRN_INFO_SUPPORT_APACHE_ARROW:
    if (!valuebuf &&
        !(valuebuf = grn_obj_open(ctx, GRN_BULK, 0, GRN_DB_BOOL))) {
      ERR(GRN_INVALID_ARGUMENT,
          "%s[support-apache-arrow] failed to allocate value buffer",
          tag);
      goto exit;
    }
#ifdef GRN_WITH_APACHE_ARROW
    GRN_BOOL_PUT(ctx, valuebuf, GRN_TRUE);
#else  /* GRN_WITH_APACHE_ARROW */
    GRN_BOOL_PUT(ctx, valuebuf, GRN_FALSE);
#endif /* GRN_WITH_APACHE_ARROW */
    break;
  default:
    if (!obj) {
      ERR(GRN_INVALID_ARGUMENT, "%s obj is NULL", tag);
      goto exit;
    }
    switch (type) {
    case GRN_INFO_ENCODING:
      if (!valuebuf) {
        if (!(valuebuf = grn_obj_open(ctx, GRN_BULK, 0, 0))) {
          ERR(GRN_INVALID_ARGUMENT,
              "%s[encoding] failed to allocate value buffer",
              tag);
          goto exit;
        }
      }
      {
        grn_encoding enc;
        if (obj->header.type == GRN_DB) {
          obj = ((grn_db *)obj)->keys;
        }
        switch (obj->header.type) {
        case GRN_TABLE_PAT_KEY:
          enc = ((grn_pat *)obj)->encoding;
          grn_bulk_write(ctx,
                         valuebuf,
                         (const char *)&enc,
                         sizeof(grn_encoding));
          break;
        case GRN_TABLE_DAT_KEY:
          enc = ((grn_dat *)obj)->encoding;
          grn_bulk_write(ctx,
                         valuebuf,
                         (const char *)&enc,
                         sizeof(grn_encoding));
          break;
        case GRN_TABLE_HASH_KEY:
          enc = ((grn_hash *)obj)->encoding;
          grn_bulk_write(ctx,
                         valuebuf,
                         (const char *)&enc,
                         sizeof(grn_encoding));
          break;
        default:
          ERR(GRN_INVALID_ARGUMENT,
              "%s[encoding] target object must be one of %s, %s or %s: %s",
              tag,
              grn_obj_type_to_string(GRN_TABLE_HASH_KEY),
              grn_obj_type_to_string(GRN_TABLE_PAT_KEY),
              grn_obj_type_to_string(GRN_TABLE_DAT_KEY),
              grn_obj_type_to_string(obj->header.type));
          break;
        }
      }
      break;
    case GRN_INFO_SOURCE:
      if (!valuebuf) {
        if (!(valuebuf = grn_obj_open(ctx, GRN_BULK, 0, 0))) {
          ERR(GRN_INVALID_ARGUMENT,
              "%s[source] failed to allocate value buffer",
              tag);
          goto exit;
        }
      }
      if (!GRN_DB_OBJP(obj)) {
        ERR(GRN_INVALID_ARGUMENT,
            "%s[source] target object must be a grn_db_obj: %s",
            tag,
            grn_obj_type_to_string(obj->header.type));
        goto exit;
      }
      grn_bulk_write(ctx,
                     valuebuf,
                     DB_OBJ(obj)->source,
                     DB_OBJ(obj)->source_size);
      break;
    case GRN_INFO_DEFAULT_TOKENIZER:
      switch (DB_OBJ(obj)->header.type) {
      case GRN_TABLE_HASH_KEY:
        valuebuf = ((grn_hash *)obj)->tokenizer.proc;
        break;
      case GRN_TABLE_PAT_KEY:
        valuebuf = ((grn_pat *)obj)->tokenizer.proc;
        break;
      case GRN_TABLE_DAT_KEY:
        valuebuf = ((grn_dat *)obj)->tokenizer.proc;
        break;
      }
      break;
    case GRN_INFO_NORMALIZER:
      {
        grn_obj *normalizers = NULL;
        switch (obj->header.type) {
        case GRN_TABLE_HASH_KEY:
          normalizers = &(((grn_hash *)obj)->normalizers);
          break;
        case GRN_TABLE_PAT_KEY:
          normalizers = &(((grn_pat *)obj)->normalizers);
          break;
        case GRN_TABLE_DAT_KEY:
          normalizers = &(((grn_dat *)obj)->normalizers);
          break;
        default:
          break;
        }
        if (normalizers &&
            GRN_BULK_VSIZE(normalizers) >= sizeof(grn_table_module)) {
          grn_table_module *module =
            (grn_table_module *)GRN_BULK_HEAD(normalizers);
          valuebuf = module->proc;
        }
      }
      break;
    case GRN_INFO_NORMALIZERS:
      if (!valuebuf) {
        if (!(valuebuf = grn_obj_open(ctx, GRN_PVECTOR, 0, 0))) {
          ERR(GRN_NO_MEMORY_AVAILABLE,
              "%s[normalizers] failed to allocate value buffer",
              tag);
          goto exit;
        }
      }
      {
        grn_obj *normalizers = NULL;
        switch (obj->header.type) {
        case GRN_TABLE_HASH_KEY:
          normalizers = &(((grn_hash *)obj)->normalizers);
          break;
        case GRN_TABLE_PAT_KEY:
          normalizers = &(((grn_pat *)obj)->normalizers);
          break;
        case GRN_TABLE_DAT_KEY:
          normalizers = &(((grn_dat *)obj)->normalizers);
          break;
        default:
          ERR(GRN_INVALID_ARGUMENT,
              "%s[normalizers] target object must be one of %s, %s and %s: %s",
              tag,
              grn_obj_type_to_string(GRN_TABLE_HASH_KEY),
              grn_obj_type_to_string(GRN_TABLE_PAT_KEY),
              grn_obj_type_to_string(GRN_TABLE_DAT_KEY),
              grn_obj_type_to_string(obj->header.type));
          break;
        }
        if (normalizers) {
          grn_table_module *raw_normalizers =
            (grn_table_module *)GRN_BULK_HEAD(normalizers);
          size_t n = GRN_BULK_VSIZE(normalizers) / sizeof(grn_table_module);
          size_t i;
          for (i = 0; i < n; i++) {
            grn_obj *normalizer = raw_normalizers[i].proc;
            GRN_PTR_PUT(ctx, valuebuf, normalizer);
          }
        }
      }
      break;
    case GRN_INFO_TOKEN_FILTERS:
      if (!valuebuf) {
        if (!(valuebuf = grn_obj_open(ctx, GRN_PVECTOR, 0, 0))) {
          ERR(GRN_NO_MEMORY_AVAILABLE,
              "%s[token-filters] failed to allocate value buffer",
              tag);
          goto exit;
        }
      }
      {
        grn_obj *token_filters = NULL;
        switch (obj->header.type) {
        case GRN_TABLE_HASH_KEY:
          token_filters = &(((grn_hash *)obj)->token_filter_procs);
          break;
        case GRN_TABLE_PAT_KEY:
          token_filters = &(((grn_pat *)obj)->token_filter_procs);
          break;
        case GRN_TABLE_DAT_KEY:
          token_filters = &(((grn_dat *)obj)->token_filter_procs);
          break;
        default:
          ERR(GRN_INVALID_ARGUMENT,
              "[info][get][token-filters] target object must be one of "
              "%s, %s or %s: %s",
              grn_obj_type_to_string(GRN_TABLE_HASH_KEY),
              grn_obj_type_to_string(GRN_TABLE_PAT_KEY),
              grn_obj_type_to_string(GRN_TABLE_DAT_KEY),
              grn_obj_type_to_string(obj->header.type));
          break;
        }
        if (token_filters) {
          grn_bulk_write(ctx,
                         valuebuf,
                         GRN_BULK_HEAD(token_filters),
                         GRN_BULK_VSIZE(token_filters));
        }
      }
      break;
    case GRN_INFO_GENERATOR:
      if (!valuebuf) {
        if (!(valuebuf = grn_obj_open(ctx, GRN_DB_TEXT, 0, 0))) {
          ERR(GRN_NO_MEMORY_AVAILABLE,
              "%s[generator] failed to allocate value buffer",
              tag);
          goto exit;
        }
      }
      {
        grn_raw_string *generator = NULL;
        switch (obj->header.type) {
        case GRN_COLUMN_FIX_SIZE:
          generator = &(((grn_ra *)obj)->generator);
          break;
        case GRN_COLUMN_VAR_SIZE:
          generator = &(((grn_ja *)obj)->generator);
          break;
        default:
          break;
        }
        if (generator) {
          GRN_TEXT_PUT(ctx, valuebuf, generator->value, generator->length);
        } else {
          ERR(GRN_INVALID_ARGUMENT,
              "%s[generator] target object must be one of %s or %s: %s",
              tag,
              grn_obj_type_to_string(GRN_COLUMN_FIX_SIZE),
              grn_obj_type_to_string(GRN_COLUMN_VAR_SIZE),
              grn_obj_type_to_string(obj->header.type));
        }
      }
      break;
    default:
      /* todo */
      break;
    }
  }
exit:
  GRN_API_RETURN(valuebuf);
}

static void
update_source_hook(grn_ctx *ctx, grn_obj *obj)
{
  grn_id *s = DB_OBJ(obj)->source;
  int i, n = DB_OBJ(obj)->source_size / sizeof(grn_id);
  grn_obj_default_set_value_hook_data hook_data = {DB_OBJ(obj)->id, 0};
  grn_obj *source, data;
  GRN_TEXT_INIT(&data, GRN_OBJ_DO_SHALLOW_COPY);
  GRN_TEXT_SET_REF(&data, &hook_data, sizeof(hook_data));
  for (i = 1; i <= n; i++, s++) {
    hook_data.section = i;
    if ((source = grn_ctx_at(ctx, *s))) {
      switch (source->header.type) {
      case GRN_TABLE_HASH_KEY:
      case GRN_TABLE_PAT_KEY:
      case GRN_TABLE_DAT_KEY:
        grn_obj_add_hook(ctx, source, GRN_HOOK_INSERT, 0, NULL, &data);
        grn_obj_add_hook(ctx, source, GRN_HOOK_DELETE, 0, NULL, &data);
        break;
      case GRN_COLUMN_FIX_SIZE:
      case GRN_COLUMN_VAR_SIZE:
      case GRN_COLUMN_INDEX:
        grn_obj_add_hook(ctx, source, GRN_HOOK_SET, 0, NULL, &data);
        break;
      default:
        /* invalid target */
        break;
      }
      grn_obj_unref(ctx, source);
    }
  }
  grn_obj_close(ctx, &data);
}

static void
del_hook(grn_ctx *ctx, grn_obj *obj, grn_hook_entry entry, grn_id target_id)
{
  grn_obj offsets;
  GRN_INT32_INIT(&offsets, GRN_OBJ_VECTOR);

  int i;
  grn_hook *hook;
  for (i = 0, hook = DB_OBJ(obj)->hooks[entry]; hook; i++, hook = hook->next) {
    if (hook->proc) {
      continue;
    }
    if (hook->data_size != sizeof(grn_obj_default_set_value_hook_data)) {
      continue;
    }
    grn_obj_default_set_value_hook_data *data =
      (grn_obj_default_set_value_hook_data *)GRN_NEXT_ADDR(hook);
    if (data->target == target_id) {
      GRN_INT32_PUT(ctx, &offsets, i);
    }
  }

  int n = GRN_INT32_VECTOR_SIZE(&offsets);
  for (i = 0; i < n; i++) {
    /* This must be larger -> smaller order. If we use smaller ->
     * larger order, offset is changed. */
    int offset = GRN_INT32_VALUE_AT(&offsets, n - i - 1);
    grn_obj_delete_hook(ctx, obj, entry, offset);
  }

  GRN_OBJ_FIN(ctx, &offsets);
}

static void
delete_source_hook(grn_ctx *ctx, grn_obj *obj)
{
  grn_id id = DB_OBJ(obj)->id;
  grn_id *source_ids = DB_OBJ(obj)->source;
  int i, n = DB_OBJ(obj)->source_size / sizeof(grn_id);
  for (i = 0; i < n; i++) {
    grn_id source_id = source_ids[i];
    grn_obj *source = grn_ctx_at(ctx, source_id);
    if (!source) {
      ERRCLR(ctx);
      continue;
    }

    switch (source->header.type) {
    case GRN_TABLE_HASH_KEY:
    case GRN_TABLE_PAT_KEY:
    case GRN_TABLE_DAT_KEY:
      del_hook(ctx, source, GRN_HOOK_INSERT, id);
      del_hook(ctx, source, GRN_HOOK_DELETE, id);
      break;
    case GRN_COLUMN_FIX_SIZE:
    case GRN_COLUMN_VAR_SIZE:
      del_hook(ctx, source, GRN_HOOK_SET, id);
      break;
    default:
      /* invalid target */
      break;
    }
  }
}

/* This should be used only when the target object can't be opened. If
 * the target object can be opened, use delete_source_hook() instead. */
/* static void */
static void
delete_source_hook_full_scan(grn_ctx *ctx, grn_id target_id, uint32_t flags)
{
  bool is_close_opened_object_mode = false;
  if (grn_thread_get_limit() == 1) {
    is_close_opened_object_mode = true;
  }

  GRN_DB_EACH_SPEC_BEGIN(ctx, cursor, id, spec)
  {
    if (id == target_id) {
      continue;
    }

    bool may_have_source = false;
    switch (spec->header.type) {
    case GRN_TABLE_HASH_KEY:
    case GRN_TABLE_PAT_KEY:
    case GRN_TABLE_DAT_KEY:
    case GRN_TABLE_NO_KEY:
    case GRN_COLUMN_VAR_SIZE:
    case GRN_COLUMN_FIX_SIZE:
      may_have_source = true;
      break;
    default:
      break;
    }
    if (!may_have_source) {
      continue;
    }

    if (is_close_opened_object_mode) {
      grn_ctx_push_temporary_open_space(ctx);
    }

    /* TODO: We should not access to internal variable in
     * GRN_DB_EACH_SPEC_BEGIN(). */
    const char *raw_hooks;
    uint32_t size = grn_vector_get_element(ctx,
                                           &decoded_spec,
                                           GRN_SERIALIZED_SPEC_INDEX_HOOK,
                                           &raw_hooks,
                                           NULL,
                                           NULL);

    grn_obj *source = NULL;
    /* TODO: Unify with grn_hook_unpack() */
    grn_hook_entry entry;
    const uint8_t *current = (const uint8_t *)raw_hooks;
    const uint8_t *end = current + size;
    for (entry = 0; entry < GRN_N_HOOK_ENTRIES && ctx->rc == GRN_SUCCESS;
         entry++) {
      int i;
      for (i = 0; true; i++) {
        uint32_t hook_proc_id_plus_one;
        GRN_B_DEC(hook_proc_id_plus_one, current);
        if (hook_proc_id_plus_one == 0) {
          break;
        }
        grn_id hook_proc_id = hook_proc_id_plus_one - 1;
        if (current >= end) {
          break;
        }
        uint32_t hold_size;
        GRN_B_DEC(hold_size, current);
        if (current >= end) {
          break;
        }
        if (current + hold_size >= end) {
          break;
        }
        if (hook_proc_id == GRN_ID_NIL) {
          grn_obj_default_set_value_hook_data *data =
            (grn_obj_default_set_value_hook_data *)current;
          if (data->target == target_id) {
            if (!source) {
              source = grn_ctx_at(ctx, id);
              if (!source) {
                break;
              }
            }
            grn_obj_delete_hook(ctx, source, entry, i);
            if (ctx->rc != GRN_SUCCESS) {
              break;
            }
          }
        }
        current += hold_size;
      }
    }

    if (is_close_opened_object_mode) {
      grn_ctx_pop_temporary_open_space(ctx);
    }
  }
  GRN_DB_EACH_SPEC_END(ctx, cursor);

  return;
}

grn_rc
grn_hook_pack(grn_ctx *ctx, grn_db_obj *obj, grn_obj *buf)
{
  grn_rc rc;
  grn_hook_entry e;
  for (e = 0; e < GRN_N_HOOK_ENTRIES; e++) {
    grn_hook *hooks;
    for (hooks = obj->hooks[e]; hooks; hooks = hooks->next) {
      grn_id id = hooks->proc ? hooks->proc->obj.id : 0;
      if ((rc = grn_text_benc(ctx, buf, id + 1))) {
        goto exit;
      }
      if ((rc = grn_text_benc(ctx, buf, hooks->data_size))) {
        goto exit;
      }
      if ((rc = grn_bulk_write(ctx,
                               buf,
                               (char *)GRN_NEXT_ADDR(hooks),
                               hooks->data_size))) {
        goto exit;
      }
    }
    if ((rc = grn_text_benc(ctx, buf, 0))) {
      goto exit;
    }
  }
exit:
  return rc;
}

static grn_rc
grn_hook_unpack(grn_ctx *ctx,
                grn_db_obj *obj,
                const char *buf,
                uint32_t buf_size)
{
  grn_hook_entry e;
  const uint8_t *p = (uint8_t *)buf, *pe = p + buf_size;
  for (e = 0; e < GRN_N_HOOK_ENTRIES; e++) {
    grn_hook *new, **last = &obj->hooks[e];
    for (;;) {
      grn_id id;
      uint32_t data_size;
      GRN_B_DEC(id, p);
      if (!id--) {
        break;
      }
      if (p >= pe) {
        return GRN_FILE_CORRUPT;
      }
      GRN_B_DEC(data_size, p);
      if (p >= pe) {
        return GRN_FILE_CORRUPT;
      }
      if (!(new = GRN_MALLOC(sizeof(grn_hook) + data_size))) {
        return GRN_NO_MEMORY_AVAILABLE;
      }
      if (id) {
        new->proc = (grn_proc *)grn_ctx_at(ctx, id);
        if (!new->proc) {
          GRN_FREE(new);
          return ctx->rc;
        }
      } else {
        new->proc = NULL;
      }
      if ((new->data_size = data_size)) {
        grn_memcpy(GRN_NEXT_ADDR(new), p, data_size);
        p += data_size;
      }
      *last = new;
      last = &new->next;
      if (p >= pe) {
        return GRN_FILE_CORRUPT;
      }
    }
    *last = NULL;
  }
  return GRN_SUCCESS;
}

static void
grn_table_modules_pack(grn_ctx *ctx, grn_obj *table_modules, grn_obj *buffer)
{
  grn_table_module *raw_table_modules =
    (grn_table_module *)GRN_BULK_HEAD(table_modules);
  size_t n = GRN_BULK_VSIZE(table_modules) / sizeof(grn_table_module);
  size_t i;
  for (i = 0; i < n; i++) {
    grn_obj *proc = raw_table_modules[i].proc;
    grn_id proc_id = grn_obj_id(ctx, proc);
    GRN_RECORD_PUT(ctx, buffer, proc_id);
  }
}

static void
grn_generator_pack(grn_ctx *ctx, grn_raw_string generator, grn_obj *buffer)
{
  GRN_TEXT_PUT(ctx, buffer, generator.value, generator.length);
}

static grn_raw_string
grn_generator_unpack(grn_ctx *ctx, grn_obj *spec_vector, uint32_t index)
{
  grn_raw_string generator;
  GRN_RAW_STRING_INIT(generator);
  if (grn_vector_size(ctx, spec_vector) <= index) {
    return generator;
  }

  generator.length = grn_vector_get_element(ctx,
                                            spec_vector,
                                            index,
                                            &(generator.value),
                                            NULL,
                                            NULL);
  return generator;
}

static grn_bool
grn_obj_encoded_spec_equal(grn_ctx *ctx,
                           grn_obj *encoded_spec1,
                           grn_obj *encoded_spec2)
{
  unsigned int i, n_elements;

  if (encoded_spec1->header.type != GRN_VECTOR) {
    return GRN_FALSE;
  }

  if (encoded_spec1->header.type != encoded_spec2->header.type) {
    return GRN_FALSE;
  }

  n_elements = grn_vector_size(ctx, encoded_spec1);
  if (grn_vector_size(ctx, encoded_spec2) != n_elements) {
    return GRN_FALSE;
  }

  for (i = 0; i < n_elements; i++) {
    const char *content1;
    const char *content2;
    unsigned int content_size1;
    unsigned int content_size2;
    uint32_t weight1;
    uint32_t weight2;
    grn_id domain1;
    grn_id domain2;

    content_size1 = grn_vector_get_element(ctx,
                                           encoded_spec1,
                                           i,
                                           &content1,
                                           &weight1,
                                           &domain1);
    content_size2 = grn_vector_get_element(ctx,
                                           encoded_spec2,
                                           i,
                                           &content2,
                                           &weight2,
                                           &domain2);
    if (content_size1 != content_size2) {
      return GRN_FALSE;
    }
    if (memcmp(content1, content2, content_size1) != 0) {
      return GRN_FALSE;
    }
    if (weight1 != weight2) {
      return GRN_FALSE;
    }
    if (domain1 != domain2) {
      return GRN_FALSE;
    }
  }

  return GRN_TRUE;
}

void
grn_obj_spec_save(grn_ctx *ctx, grn_db_obj *obj)
{
  grn_db *s;
  grn_obj v, *b;
  grn_obj_spec spec;
  grn_bool need_update = GRN_TRUE;

  if (obj->id & GRN_OBJ_TMP_OBJECT) {
    return;
  }
  if (!ctx->impl || !GRN_DB_OBJP(obj)) {
    return;
  }
  if (!(s = (grn_db *)ctx->impl->db) || !s->specs) {
    return;
  }
  if (obj->header.type == GRN_PROC && obj->range == GRN_ID_NIL) {
    return;
  }
  GRN_OBJ_INIT(&v, GRN_VECTOR, 0, GRN_DB_TEXT);
  if (!(b = grn_vector_body(ctx, &v))) {
    return;
  }
  spec.header = obj->header;
  spec.range = obj->range;
  grn_bulk_write(ctx, b, (void *)&spec, sizeof(grn_obj_spec));
  grn_vector_delimit(ctx, &v, 0, 0);
  if (obj->header.flags & GRN_OBJ_CUSTOM_NAME) {
    GRN_TEXT_PUTS(ctx, b, grn_obj_path(ctx, (grn_obj *)obj));
  }
  grn_vector_delimit(ctx, &v, 0, 0);
  grn_bulk_write(ctx, b, obj->source, obj->source_size);
  grn_vector_delimit(ctx, &v, 0, 0);
  grn_hook_pack(ctx, obj, b);
  grn_vector_delimit(ctx, &v, 0, 0);
  switch (obj->header.type) {
  case GRN_TABLE_HASH_KEY:
    grn_table_modules_pack(ctx, &(((grn_hash *)obj)->token_filters), b);
    grn_vector_delimit(ctx, &v, 0, 0);
    grn_table_modules_pack(ctx, &(((grn_hash *)obj)->normalizers), b);
    grn_vector_delimit(ctx, &v, 0, 0);
    break;
  case GRN_TABLE_PAT_KEY:
    grn_table_modules_pack(ctx, &(((grn_pat *)obj)->token_filters), b);
    grn_vector_delimit(ctx, &v, 0, 0);
    grn_table_modules_pack(ctx, &(((grn_pat *)obj)->normalizers), b);
    grn_vector_delimit(ctx, &v, 0, 0);
    break;
  case GRN_TABLE_DAT_KEY:
    grn_table_modules_pack(ctx, &(((grn_dat *)obj)->token_filters), b);
    grn_vector_delimit(ctx, &v, 0, 0);
    grn_table_modules_pack(ctx, &(((grn_dat *)obj)->normalizers), b);
    grn_vector_delimit(ctx, &v, 0, 0);
    break;
  case GRN_COLUMN_FIX_SIZE:
    grn_generator_pack(ctx, ((grn_ra *)obj)->generator, b);
    grn_vector_delimit(ctx, &v, 0, 0);
    break;
  case GRN_COLUMN_VAR_SIZE:
    grn_generator_pack(ctx, ((grn_ja *)obj)->generator, b);
    grn_vector_delimit(ctx, &v, 0, 0);
    break;
  case GRN_EXPR:
    grn_expr_pack(ctx, b, (grn_obj *)obj);
    grn_vector_delimit(ctx, &v, 0, 0);
    break;
  }

  {
    grn_io_win jw;
    uint32_t current_spec_raw_len;
    char *current_spec_raw;

    current_spec_raw =
      grn_ja_ref(ctx, s->specs, obj->id, &jw, &current_spec_raw_len);
    if (current_spec_raw) {
      grn_rc rc;
      grn_obj current_spec;

      GRN_OBJ_INIT(&current_spec, GRN_VECTOR, 0, GRN_DB_TEXT);
      rc = grn_vector_unpack(ctx,
                             &current_spec,
                             current_spec_raw,
                             current_spec_raw_len,
                             0,
                             NULL);
      if (rc == GRN_SUCCESS) {
        need_update = !grn_obj_encoded_spec_equal(ctx, &v, &current_spec);
      }
      GRN_OBJ_FIN(ctx, &current_spec);
      grn_ja_unref(ctx, &jw);
    }
  }

  if (!need_update) {
    grn_obj_close(ctx, &v);
    return;
  }

  {
    const char *name;
    uint32_t name_size = 0;
    const char *range_name = NULL;
    uint32_t range_name_size = 0;

    name = _grn_table_key(ctx, s->keys, obj->id, &name_size);
    switch (obj->header.type) {
    case GRN_TABLE_HASH_KEY:
    case GRN_TABLE_PAT_KEY:
    case GRN_TABLE_DAT_KEY:
    case GRN_TABLE_NO_KEY:
    case GRN_COLUMN_FIX_SIZE:
    case GRN_COLUMN_VAR_SIZE:
    case GRN_COLUMN_INDEX:
      if (obj->range != GRN_ID_NIL) {
        range_name = _grn_table_key(ctx, s->keys, obj->range, &range_name_size);
      }
      break;
    default:
      break;
    }
    /* TODO: reduce log level. */
    GRN_LOG(ctx,
            GRN_LOG_NOTICE,
            "spec:%u:update:%.*s:%u(%s):%u%s%.*s%s",
            obj->id,
            name_size,
            name,
            obj->header.type,
            grn_obj_type_to_string(obj->header.type),
            obj->range,
            range_name_size == 0 ? "" : "(",
            range_name_size,
            range_name,
            range_name_size == 0 ? "" : ")");
  }
  grn_ja_putv(ctx, s->specs, obj->id, &v, GRN_OBJ_SET);
  grn_obj_close(ctx, &v);
}

static inline void
grn_obj_set_info_source_invalid_lexicon_error(grn_ctx *ctx,
                                              const char *message,
                                              grn_obj *actual_type,
                                              grn_obj *expected_type,
                                              grn_obj *index_column,
                                              grn_obj *source)
{
  char actual_type_name[GRN_TABLE_MAX_KEY_SIZE];
  int actual_type_name_size;
  char expected_type_name[GRN_TABLE_MAX_KEY_SIZE];
  int expected_type_name_size;
  char index_column_name[GRN_TABLE_MAX_KEY_SIZE];
  int index_column_name_size;
  char source_name[GRN_TABLE_MAX_KEY_SIZE];
  int source_name_size;

  actual_type_name_size =
    grn_obj_name(ctx, actual_type, actual_type_name, GRN_TABLE_MAX_KEY_SIZE);
  expected_type_name_size = grn_obj_name(ctx,
                                         expected_type,
                                         expected_type_name,
                                         GRN_TABLE_MAX_KEY_SIZE);
  index_column_name_size =
    grn_obj_name(ctx, index_column, index_column_name, GRN_TABLE_MAX_KEY_SIZE);

  source_name_size =
    grn_obj_name(ctx, source, source_name, GRN_TABLE_MAX_KEY_SIZE);
  if (grn_obj_is_table(ctx, source)) {
    source_name[source_name_size] = '\0';
    grn_strncat(source_name,
                GRN_TABLE_MAX_KEY_SIZE,
                "._key",
                GRN_TABLE_MAX_KEY_SIZE - source_name_size - 1);
    source_name_size = strlen(source_name);
  }

  ERR(GRN_INVALID_ARGUMENT,
      "[column][index][source] %s: "
      "<%.*s> -> <%.*s>: "
      "index-column:<%.*s> "
      "source:<%.*s>",
      message,
      actual_type_name_size,
      actual_type_name,
      expected_type_name_size,
      expected_type_name,
      index_column_name_size,
      index_column_name,
      source_name_size,
      source_name);
}

static inline grn_rc
grn_obj_set_info_source_validate(grn_ctx *ctx, grn_obj *obj, grn_obj *value)
{
  grn_id lexicon_id;
  grn_obj *lexicon = NULL;
  grn_id lexicon_domain_id;
  grn_obj *lexicon_domain = NULL;
  bool lexicon_domain_is_table = false;
  grn_bool lexicon_have_tokenizer;
  grn_bool is_full_text_search_index;
  grn_id *source_ids;
  int i, n_source_ids;

  lexicon_id = obj->header.domain;
  lexicon = grn_ctx_at(ctx, lexicon_id);
  if (!lexicon) {
    goto exit;
  }

  lexicon_domain_id = lexicon->header.domain;
  lexicon_domain = grn_ctx_at(ctx, lexicon_domain_id);
  if (!lexicon_domain) {
    goto exit;
  }
  lexicon_domain_is_table = grn_obj_is_table(ctx, lexicon_domain);
  {
    grn_obj *tokenizer;
    grn_table_get_info(ctx, lexicon, NULL, NULL, &tokenizer, NULL, NULL);
    lexicon_have_tokenizer = (tokenizer != NULL);

    is_full_text_search_index =
      (grn_obj_is_index_column(ctx, obj) &&
       (obj->header.flags & GRN_OBJ_WITH_POSITION) && lexicon_have_tokenizer &&
       grn_obj_id(ctx, tokenizer) != GRN_DB_DELIMIT);
  }

  source_ids = (grn_id *)GRN_BULK_HEAD(value);
  n_source_ids = GRN_BULK_VSIZE(value) / sizeof(grn_id);

  if (n_source_ids > 1 && !(obj->header.flags & GRN_OBJ_WITH_SECTION)) {
    char index_name[GRN_TABLE_MAX_KEY_SIZE];
    int index_name_size;
    index_name_size =
      grn_obj_name(ctx, obj, index_name, GRN_TABLE_MAX_KEY_SIZE);
    ERR(GRN_INVALID_ARGUMENT,
        "grn_obj_set_info(): GRN_INFO_SOURCE: "
        "multi column index must be created with WITH_SECTION flag: <%.*s>",
        index_name_size,
        index_name);
    goto exit;
  }

  if (is_full_text_search_index) {
    grn_bool have_vector_source_column = GRN_FALSE;

    for (i = 0; i < n_source_ids; i++) {
      grn_obj *source;

      source = grn_ctx_at(ctx, source_ids[i]);
      bool source_is_vector_column = grn_obj_is_vector_column(ctx, source);
      if (!grn_obj_is_temporary(ctx, source)) {
        grn_obj_unlink(ctx, source);
      }
      if (!source_is_vector_column) {
        continue;
      }

      have_vector_source_column = GRN_TRUE;
      if (!(obj->header.flags & GRN_OBJ_WITH_SECTION)) {
        char index_name[GRN_TABLE_MAX_KEY_SIZE];
        int index_name_size;
        index_name_size =
          grn_obj_name(ctx, obj, index_name, GRN_TABLE_MAX_KEY_SIZE);
        ERR(GRN_INVALID_ARGUMENT,
            "grn_obj_set_info(): GRN_INFO_SOURCE: "
            "full text index for vector column "
            "must be created with WITH_SECTION flag: <%.*s>",
            index_name_size,
            index_name);
        goto exit;
      }
    }

    if (have_vector_source_column && n_source_ids > 1) {
      char index_name[GRN_TABLE_MAX_KEY_SIZE];
      int index_name_size;
      index_name_size =
        grn_obj_name(ctx, obj, index_name, GRN_TABLE_MAX_KEY_SIZE);
      ERR(
        GRN_INVALID_ARGUMENT,
        "grn_obj_set_info(): GRN_INFO_SOURCE: "
        "multi column full text index with vector column isn't supported yet: "
        "<%.*s>",
        index_name_size,
        index_name);
      goto exit;
    }
  }

  for (i = 0; i < n_source_ids; i++) {
    grn_id source_id = source_ids[i];
    grn_obj *source;
    grn_id source_type_id;
    grn_obj *source_type;

    source = grn_ctx_at(ctx, source_id);
    if (!source) {
      continue;
    }
    if (grn_obj_is_table(ctx, source)) {
      source_type_id = source->header.domain;
    } else {
      source_type_id = DB_OBJ(source)->range;
    }
    source_type = grn_ctx_at(ctx, source_type_id);
    if (!lexicon_have_tokenizer) {
      if (grn_obj_is_table(ctx, source_type)) {
        if (lexicon_id != source_type_id) {
          grn_obj_set_info_source_invalid_lexicon_error(
            ctx,
            "index table must equal to source type",
            lexicon,
            source_type,
            obj,
            source);
        }
      } else {
        if (!grn_type_id_is_compatible(ctx,
                                       lexicon_domain_id,
                                       source_type_id)) {
          grn_obj_set_info_source_invalid_lexicon_error(
            ctx,
            "index table's key must equal source type",
            lexicon_domain,
            source_type,
            obj,
            source);
        }
      }
    }
    grn_obj_unref(ctx, source_type);
    grn_obj_unref(ctx, source);
    if (ctx->rc != GRN_SUCCESS) {
      goto exit;
    }
  }

exit:
  if (lexicon_domain && lexicon_domain_is_table &&
      !grn_obj_is_temporary(ctx, lexicon_domain)) {
    grn_obj_unlink(ctx, lexicon_domain);
  }
  if (lexicon && !grn_obj_is_temporary(ctx, lexicon)) {
    grn_obj_unlink(ctx, lexicon);
  }

  return ctx->rc;
}

static inline void
grn_obj_set_info_source_log(grn_ctx *ctx, grn_obj *obj, grn_obj *value)
{
  grn_obj buf;
  grn_id *vp = (grn_id *)GRN_BULK_HEAD(value);
  uint32_t vs = GRN_BULK_VSIZE(value), s = 0;
  grn_id id;
  const char *n;

  id = DB_OBJ(obj)->id;
  n = _grn_table_key(ctx, ctx->impl->db, id, &s);
  GRN_TEXT_INIT(&buf, 0);
  GRN_TEXT_PUT(ctx, &buf, n, s);
  GRN_TEXT_PUTC(ctx, &buf, ' ');
  while (vs) {
    n = _grn_table_key(ctx, ctx->impl->db, *vp++, &s);
    GRN_TEXT_PUT(ctx, &buf, n, s);
    vs -= sizeof(grn_id);
    if (vs) {
      GRN_TEXT_PUTC(ctx, &buf, ',');
    }
  }
  GRN_LOG(ctx,
          GRN_LOG_NOTICE,
          "DDL:%u:set_source %.*s",
          id,
          (int)GRN_BULK_VSIZE(&buf),
          GRN_BULK_HEAD(&buf));
  GRN_OBJ_FIN(ctx, &buf);
}

static inline grn_rc
grn_obj_set_info_source_update(grn_ctx *ctx, grn_obj *obj, grn_obj *value)
{
  void *v = GRN_BULK_HEAD(value);
  uint32_t s = GRN_BULK_VSIZE(value);
  if (s) {
    void *v2 = GRN_MALLOC(s);
    if (!v2) {
      return ctx->rc;
    }
    grn_memcpy(v2, v, s);
    if (DB_OBJ(obj)->source) {
      GRN_FREE(DB_OBJ(obj)->source);
    }
    DB_OBJ(obj)->source = v2;
    DB_OBJ(obj)->source_size = s;
    grn_obj_spec_save(ctx, DB_OBJ(obj));

    switch (obj->header.type) {
    case GRN_COLUMN_FIX_SIZE:
      update_source_hook(ctx, obj);
      if (((grn_ra *)obj)->generator.length > 0) {
        grn_generated_column_build(ctx, obj);
      }
      break;
    case GRN_COLUMN_VAR_SIZE:
      update_source_hook(ctx, obj);
      if (((grn_ja *)obj)->generator.length > 0) {
        grn_generated_column_build(ctx, obj);
      } else {
        grn_token_column_build(ctx, obj);
      }
      break;
    case GRN_COLUMN_INDEX:
      update_source_hook(ctx, obj);
      grn_index_column_build(ctx, obj);
      break;
    default:
      break;
    }
  } else {
    DB_OBJ(obj)->source = NULL;
    DB_OBJ(obj)->source_size = 0;
    grn_obj_spec_save(ctx, DB_OBJ(obj));
  }

  return GRN_SUCCESS;
}

static inline grn_rc
grn_obj_set_info_source(grn_ctx *ctx, grn_obj *obj, grn_obj *value)
{
  grn_rc rc;

  rc = grn_obj_set_info_source_validate(ctx, obj, value);
  if (rc != GRN_SUCCESS) {
    return rc;
  }
  grn_obj_set_info_source_log(ctx, obj, value);
  rc = grn_obj_set_info_source_update(ctx, obj, value);
  if (rc != GRN_SUCCESS) {
    return rc;
  }

  return rc;
}

static grn_bool
grn_obj_set_info_is_funcall_call_bulk(grn_ctx *ctx, grn_obj *bulk)
{
  const char *current;
  const char *end;

  current = GRN_TEXT_VALUE(bulk);
  end = current + GRN_TEXT_LEN(bulk);
  while (current < end) {
    int char_length;

    char_length = grn_charlen(ctx, current, end);
    if (char_length != 1) {
      return GRN_TRUE;
    }

    if (current[0] == '(') {
      return GRN_TRUE;
    }

    current += char_length;
  }

  return GRN_FALSE;
}

static grn_rc
grn_obj_set_info_require_key_table(grn_ctx *ctx,
                                   grn_obj *table,
                                   const char *context_tag)
{
  switch (table->header.type) {
  case GRN_TABLE_HASH_KEY:
  case GRN_TABLE_PAT_KEY:
  case GRN_TABLE_DAT_KEY:
    return ctx->rc;
  default:
    ERR(GRN_INVALID_ARGUMENT,
        "%s target object must be one of "
        "GRN_TABLE_HASH_KEY, GRN_TABLE_PAT_KEY or GRN_TABLE_DAT_KEY: <%s>",
        context_tag,
        grn_obj_type_to_string(table->header.type));
    return ctx->rc;
  }
}

static grn_rc
grn_obj_set_info_table_module_raw(grn_ctx *ctx,
                                  grn_obj *table,
                                  grn_info_type type,
                                  grn_table_module *table_module,
                                  grn_id *proc_id,
                                  unsigned int i,
                                  grn_obj *module,
                                  const char *context_tag,
                                  const char *module_name)
{
  char name[GRN_TABLE_MAX_KEY_SIZE];
  unsigned int name_size;
  grn_obj *proc = NULL;
  grn_obj *expression = NULL;
  grn_obj options;

  GRN_TEXT_INIT(&options, GRN_OBJ_VECTOR);

  name_size = grn_obj_name(ctx, table, name, sizeof(name));
  if (name_size == 0) {
    grn_strcpy(name, sizeof(name), "(anonymous)");
    name_size = strlen(name);
  }
  if (grn_obj_is_text_family_bulk(ctx, module)) {
    if (GRN_TEXT_LEN(module) == 0) {
      proc = NULL;
    } else if (grn_obj_set_info_is_funcall_call_bulk(ctx, module)) {
      grn_obj *unused;
      GRN_EXPR_CREATE_FOR_QUERY(ctx, table, expression, unused);
      grn_expr_parse(ctx,
                     expression,
                     GRN_TEXT_VALUE(module),
                     GRN_TEXT_LEN(module),
                     NULL,
                     GRN_OP_MATCH,
                     GRN_OP_AND,
                     GRN_EXPR_SYNTAX_SCRIPT);
      if (ctx->rc != GRN_SUCCESS) {
        char errbuf[GRN_CTX_MSGSIZE];
        grn_strcpy(errbuf, GRN_CTX_MSGSIZE, ctx->errbuf);
        ERR(GRN_INVALID_ARGUMENT,
            "%s[%.*s] failed to parse %s options: <%.*s>: %s",
            context_tag,
            (int)name_size,
            name,
            module_name,
            (int)GRN_TEXT_LEN(module),
            GRN_TEXT_VALUE(module),
            errbuf);
        goto exit;
      }
      if (!grn_expr_is_simple_function_call(ctx, expression)) {
        ERR(GRN_INVALID_ARGUMENT,
            "%s[%.*s] must be %s(option1, option2, ...) format: <%.*s>",
            context_tag,
            (int)name_size,
            name,
            module_name,
            (int)GRN_TEXT_LEN(module),
            GRN_TEXT_VALUE(module));
        goto exit;
      }
      proc = grn_expr_simple_function_call_get_function(ctx, expression);
      grn_expr_simple_function_call_get_arguments(ctx, expression, &options);
    } else {
      proc = grn_ctx_get(ctx, GRN_TEXT_VALUE(module), GRN_TEXT_LEN(module));
      if (!proc) {
        ERR(GRN_INVALID_ARGUMENT,
            "%s[%.*s] unknown %s: <%.*s>",
            context_tag,
            (int)name_size,
            name,
            module_name,
            (int)GRN_TEXT_LEN(module),
            GRN_TEXT_VALUE(module));
        goto exit;
      }
    }
  } else {
    proc = module;
  }

  if (proc) {
    bool is_valid_proc = false;

    switch (type) {
    case GRN_INFO_DEFAULT_TOKENIZER:
      is_valid_proc = grn_obj_is_tokenizer_proc(ctx, proc);
      break;
    case GRN_INFO_NORMALIZER:
    case GRN_INFO_NORMALIZERS:
      is_valid_proc = grn_obj_is_normalizer_proc(ctx, proc);
      break;
    case GRN_INFO_TOKEN_FILTERS:
      is_valid_proc = grn_obj_is_token_filter_proc(ctx, proc);
      break;
    default:
      break;
    }

    if (!is_valid_proc) {
      char proc_name[GRN_TABLE_MAX_KEY_SIZE];
      unsigned int proc_name_size;

      proc_name_size = grn_obj_name(ctx, proc, proc_name, sizeof(proc_name));
      ERR(GRN_INVALID_ARGUMENT,
          "%s[%.*s] invalid %s: <%.*s>",
          context_tag,
          (int)name_size,
          name,
          module_name,
          (int)proc_name_size,
          proc_name);
      goto exit;
    }
  }

  if (table_module) {
    grn_table_module_set_proc(ctx, table_module, proc);
  }
  if (proc) {
    *proc_id = grn_obj_id(ctx, proc);
  } else {
    *proc_id = GRN_ID_NIL;
  }
  switch (type) {
  case GRN_INFO_DEFAULT_TOKENIZER:
    grn_table_set_default_tokenizer_options(ctx, table, &options);
    if (DB_OBJ(table)->header.type == GRN_TABLE_PAT_KEY) {
      grn_pat_cache_enable(ctx, (grn_pat *)table, GRN_TABLE_PAT_KEY_CACHE_SIZE);
    }
    break;
  case GRN_INFO_NORMALIZER:
    grn_table_set_normalizer_options(ctx, table, &options);
    break;
  case GRN_INFO_TOKEN_FILTERS:
    grn_table_set_token_filters_options(ctx, table, i, &options);
    break;
  default:
    break;
  }

exit:
  GRN_OBJ_FIN(ctx, &options);

  if (expression) {
    grn_obj_close(ctx, expression);
  }

  return ctx->rc;
}

static grn_rc
grn_obj_set_info_table_module(grn_ctx *ctx,
                              grn_obj *table,
                              grn_info_type type,
                              grn_obj *module,
                              const char *context_tag,
                              const char *module_name)
{
  grn_table_module *table_module = NULL;
  grn_id *proc_id = NULL;

  if (grn_obj_set_info_require_key_table(ctx, table, context_tag) !=
      GRN_SUCCESS) {
    return ctx->rc;
  }

  switch (DB_OBJ(table)->header.type) {
  case GRN_TABLE_HASH_KEY:
    switch (type) {
    case GRN_INFO_DEFAULT_TOKENIZER:
      table_module = &(((grn_hash *)table)->tokenizer);
      proc_id = &(((grn_hash *)table)->header.common->tokenizer);
      break;
    case GRN_INFO_NORMALIZER:
      table_module = NULL;
      proc_id = &(((grn_hash *)table)->header.common->normalizer);
      break;
    default:
      break;
    }
    break;
  case GRN_TABLE_PAT_KEY:
    switch (type) {
    case GRN_INFO_DEFAULT_TOKENIZER:
      table_module = &(((grn_pat *)table)->tokenizer);
      proc_id = &(((grn_pat *)table)->header->tokenizer);
      break;
    case GRN_INFO_NORMALIZER:
      table_module = NULL;
      proc_id = &(((grn_pat *)table)->header->normalizer);
      break;
    default:
      break;
    }
    break;
  case GRN_TABLE_DAT_KEY:
    switch (type) {
    case GRN_INFO_DEFAULT_TOKENIZER:
      table_module = &(((grn_dat *)table)->tokenizer);
      proc_id = &(((grn_dat *)table)->header->tokenizer);
      break;
    case GRN_INFO_NORMALIZER:
      table_module = NULL;
      proc_id = &(((grn_dat *)table)->header->normalizer);
      break;
    default:
      break;
    }
  default:
    break;
  }

  return grn_obj_set_info_table_module_raw(ctx,
                                           table,
                                           type,
                                           table_module,
                                           proc_id,
                                           0,
                                           module,
                                           context_tag,
                                           module_name);
}

static grn_rc
grn_obj_set_info_table_modules_text(grn_ctx *ctx,
                                    grn_obj *table,
                                    grn_info_type type,
                                    grn_obj *table_modules,
                                    grn_obj *procs,
                                    grn_obj *modules,
                                    const char *context_tag,
                                    const char *module_name)
{
  char name[GRN_TABLE_MAX_KEY_SIZE];
  unsigned int name_size;
  grn_obj *unused;
  grn_obj *expression = NULL;
  size_t i, n;
  grn_obj options;

  GRN_TEXT_INIT(&options, GRN_OBJ_VECTOR);

  name_size = grn_obj_name(ctx, table, name, sizeof(name));
  if (name_size == 0) {
    grn_strcpy(name, sizeof(name), "(anonymous)");
    name_size = strlen(name);
  }

  if (GRN_TEXT_LEN(modules) == 0) {
    goto exit;
  }

  GRN_EXPR_CREATE_FOR_QUERY(ctx, table, expression, unused);
  grn_expr_parse(ctx,
                 expression,
                 GRN_TEXT_VALUE(modules),
                 GRN_TEXT_LEN(modules),
                 NULL,
                 GRN_OP_MATCH,
                 GRN_OP_AND,
                 GRN_EXPR_SYNTAX_SCRIPT);
  if (ctx->rc != GRN_SUCCESS) {
    char errbuf[GRN_CTX_MSGSIZE];
    grn_strcpy(errbuf, GRN_CTX_MSGSIZE, ctx->errbuf);
    ERR(GRN_INVALID_ARGUMENT,
        "%s[%.*s] failed to parse %s: <%.*s>: %s",
        context_tag,
        (int)name_size,
        name,
        module_name,
        (int)GRN_TEXT_LEN(modules),
        GRN_TEXT_VALUE(modules),
        errbuf);
    goto exit;
  }
  if (!grn_expr_is_module_list(ctx, expression)) {
    ERR(GRN_INVALID_ARGUMENT,
        "%s[%.*s] must be %s(option1, option2, ...), ... format: <%.*s>",
        context_tag,
        (int)name_size,
        name,
        module_name,
        (int)GRN_TEXT_LEN(modules),
        GRN_TEXT_VALUE(modules));
    goto exit;
  }

  n = grn_expr_module_list_get_n_modules(ctx, expression);
  for (i = 0; i < n; i++) {
    grn_obj *proc;
    grn_id proc_id;

    proc = grn_expr_module_list_get_function(ctx, expression, i);
    GRN_BULK_REWIND(&options);
    grn_expr_module_list_get_arguments(ctx, expression, i, &options);

    bool is_valid_proc = false;
    switch (type) {
    case GRN_INFO_NORMALIZERS:
      is_valid_proc = grn_obj_is_normalizer_proc(ctx, proc);
      break;
    case GRN_INFO_TOKEN_FILTERS:
      is_valid_proc = grn_obj_is_token_filter_proc(ctx, proc);
      break;
    default:
      break;
    }

    if (!is_valid_proc) {
      char proc_name[GRN_TABLE_MAX_KEY_SIZE];
      unsigned int proc_name_size;

      proc_name_size = grn_obj_name(ctx, proc, proc_name, sizeof(proc_name));
      ERR(GRN_INVALID_ARGUMENT,
          "%s[%.*s] invalid %s: <%.*s>",
          context_tag,
          (int)name_size,
          name,
          module_name,
          (int)proc_name_size,
          proc_name);
      goto exit;
    }

    proc_id = grn_obj_id(ctx, proc);

    grn_table_modules_add(ctx, table_modules, proc);

    switch (type) {
    case GRN_INFO_NORMALIZERS:
      grn_table_set_normalizers_options(ctx, table, i, &options);
      break;
    case GRN_INFO_TOKEN_FILTERS:
      GRN_PTR_PUT(ctx, procs, proc);
      grn_table_set_token_filters_options(ctx, table, i, &options);
      break;
    default:
      break;
    }
  }

exit:
  GRN_OBJ_FIN(ctx, &options);

  if (expression) {
    grn_obj_close(ctx, expression);
  }

  return ctx->rc;
}

static grn_rc
grn_obj_set_info_table_modules_vector(grn_ctx *ctx,
                                      grn_obj *table,
                                      grn_info_type type,
                                      grn_obj *table_modules,
                                      grn_obj *procs,
                                      grn_obj *modules,
                                      const char *context_tag,
                                      const char *module_name)
{
  bool is_names = grn_obj_is_vector(ctx, modules);
  unsigned int n_modules;
  if (is_names) {
    n_modules = grn_vector_size(ctx, modules);
  } else {
    n_modules = GRN_PTR_VECTOR_SIZE(modules);
  }

  unsigned int i;
  for (i = 0; i < n_modules; i++) {
    grn_obj name_buffer;
    grn_obj *module;
    if (is_names) {
      const char *name;
      unsigned int name_size =
        grn_vector_get_element(ctx, modules, i, &name, NULL, NULL);
      GRN_TEXT_INIT(&name_buffer, GRN_OBJ_DO_SHALLOW_COPY);
      GRN_TEXT_SET(ctx, &name_buffer, name, name_size);
      module = &name_buffer;
    } else {
      module = GRN_PTR_VALUE_AT(modules, i);
    }

    unsigned int current_table_modules_size = GRN_BULK_VSIZE(table_modules);
    grn_bulk_space(ctx, table_modules, sizeof(grn_table_module));
    grn_table_module *table_module =
      ((grn_table_module *)GRN_BULK_HEAD(table_modules)) + i;
    grn_table_module_init(ctx, table_module, GRN_ID_NIL);
    grn_id proc_id = GRN_ID_NIL;
    grn_obj_set_info_table_module_raw(ctx,
                                      table,
                                      type,
                                      table_module,
                                      &proc_id,
                                      i,
                                      module,
                                      context_tag,
                                      module_name);
    if (ctx->rc != GRN_SUCCESS) {
      grn_table_module_fin(ctx, table_module);
      grn_bulk_truncate(ctx, table_modules, current_table_modules_size);
      return ctx->rc;
    }
    if (procs) {
      GRN_PTR_PUT(ctx, procs, table_module->proc);
    }

    if (module == &name_buffer) {
      GRN_OBJ_FIN(ctx, &name_buffer);
    }
  }

  return ctx->rc;
}

static grn_rc
grn_obj_set_info_table_modules(grn_ctx *ctx,
                               grn_obj *table,
                               grn_info_type type,
                               grn_obj *modules,
                               const char *context_tag,
                               const char *module_name,
                               const char *module_id)
{
  if (grn_obj_set_info_require_key_table(ctx, table, context_tag) !=
      GRN_SUCCESS) {
    return ctx->rc;
  }

  grn_obj *table_modules = NULL;
  grn_obj *procs = NULL;
  switch (table->header.type) {
  case GRN_TABLE_HASH_KEY:
    switch (type) {
    case GRN_INFO_NORMALIZERS:
      table_modules = &(((grn_hash *)table)->normalizers);
      break;
    case GRN_INFO_TOKEN_FILTERS:
      table_modules = &(((grn_hash *)table)->token_filters);
      procs = &(((grn_hash *)table)->token_filter_procs);
      break;
    default:
      break;
    }
    break;
  case GRN_TABLE_PAT_KEY:
    switch (type) {
    case GRN_INFO_NORMALIZERS:
      table_modules = &(((grn_pat *)table)->normalizers);
      break;
    case GRN_INFO_TOKEN_FILTERS:
      table_modules = &(((grn_pat *)table)->token_filters);
      procs = &(((grn_pat *)table)->token_filter_procs);
      break;
    default:
      break;
    }
    break;
  case GRN_TABLE_DAT_KEY:
    switch (type) {
    case GRN_INFO_NORMALIZERS:
      table_modules = &(((grn_dat *)table)->normalizers);
      break;
    case GRN_INFO_TOKEN_FILTERS:
      table_modules = &(((grn_dat *)table)->token_filters);
      procs = &(((grn_dat *)table)->token_filter_procs);
      break;
    default:
      break;
    }
  default:
    break;
  }

  grn_table_modules_rewind(ctx, table_modules);
  if (procs) {
    GRN_BULK_REWIND(procs);
  }

  if (grn_obj_is_text_family_bulk(ctx, modules)) {
    grn_obj_set_info_table_modules_text(ctx,
                                        table,
                                        type,
                                        table_modules,
                                        procs,
                                        modules,
                                        context_tag,
                                        module_name);
  } else {
    grn_obj_set_info_table_modules_vector(ctx,
                                          table,
                                          type,
                                          table_modules,
                                          procs,
                                          modules,
                                          context_tag,
                                          module_name);
  }
  if (ctx->rc != GRN_SUCCESS) {
    return ctx->rc;
  }

  {
    grn_obj names;
    GRN_TEXT_INIT(&names, 0);
    size_t n = GRN_BULK_VSIZE(table_modules) / sizeof(grn_table_module);
    size_t i;
    for (i = 0; i < n; i++) {
      grn_obj *proc =
        ((grn_table_module *)GRN_BULK_HEAD(table_modules))[i].proc;

      if (i > 0) {
        GRN_TEXT_PUTC(ctx, &names, ',');
      }

      char name[GRN_TABLE_MAX_KEY_SIZE];
      unsigned int name_size =
        grn_obj_name(ctx, proc, name, GRN_TABLE_MAX_KEY_SIZE);
      GRN_TEXT_PUT(ctx, &names, name, name_size);
    }
    grn_id table_id = DB_OBJ(table)->id;
    grn_log_level log_level =
      (table_id & GRN_OBJ_TMP_OBJECT) ? GRN_LOG_DEBUG : GRN_LOG_NOTICE;
    GRN_LOG(ctx,
            log_level,
            "DDL:%u:set_%s%s%.*s",
            DB_OBJ(table)->id,
            module_id,
            n == 0 ? "" : " ",
            (int)GRN_TEXT_LEN(&names),
            GRN_TEXT_VALUE(&names));
    GRN_OBJ_FIN(ctx, &names);
  }
  grn_obj_spec_save(ctx, DB_OBJ(table));

  return GRN_SUCCESS;
}

/* This is an internal function. Caller must pass GRN_COLUMN_FIX_SIZE
 * or GRN_COLUMN_VAR_SIZE as `obj`. This function doesn't validate
 * it. */
static grn_rc
grn_obj_set_generator(grn_ctx *ctx,
                      grn_obj *obj,
                      grn_raw_string generator,
                      const char *context_tag)
{
  grn_obj *table = grn_ctx_at(ctx, obj->header.domain);
  if (!table) {
    GRN_DEFINE_NAME(obj);
    ERR(GRN_INVALID_ARGUMENT,
        "%s belonged table doesn't exist: <%s>(%u): <%u>",
        context_tag,
        name,
        DB_OBJ(obj)->id,
        obj->header.domain);
    return ctx->rc;
  }

  grn_obj **parsed_generator = NULL;
  if (obj->header.type == GRN_COLUMN_FIX_SIZE) {
    grn_ra *ra = (grn_ra *)obj;
    grn_ra_set_generator(ctx, ra, generator);
    parsed_generator = &(ra->parsed_generator);
  } else {
    grn_ja *ja = (grn_ja *)obj;
    grn_ja_set_generator(ctx, ja, generator);
    parsed_generator = &(ja->parsed_generator);
  }
  if (ctx->rc != GRN_SUCCESS) {
    grn_obj_unref(ctx, table);
    return ctx->rc;
  }

  if (generator.length > 0) {
    grn_obj *variable;
    GRN_EXPR_CREATE_FOR_QUERY(ctx, table, *parsed_generator, variable);
    if (*parsed_generator) {
      grn_expr_parse(ctx,
                     *parsed_generator,
                     generator.value,
                     generator.length,
                     NULL,
                     GRN_OP_MATCH,
                     GRN_OP_AND,
                     GRN_EXPR_SYNTAX_SCRIPT);
      if (ctx->rc != GRN_SUCCESS) {
        GRN_DEFINE_NAME(obj);
        char errbuf[GRN_CTX_MSGSIZE];
        grn_strcpy(errbuf, GRN_CTX_MSGSIZE, ctx->errbuf);
        ERR(GRN_INVALID_ARGUMENT,
            "%s failed to parse generator: <%s>(%u): <%u>: %s",
            context_tag,
            name,
            DB_OBJ(obj)->id,
            obj->header.domain,
            errbuf);
        grn_obj_close(ctx, *parsed_generator);
        *parsed_generator = NULL;
      }
    }
    if (!*parsed_generator) {
      grn_raw_string empty_generator;
      GRN_RAW_STRING_INIT(empty_generator);
      if (obj->header.type == GRN_COLUMN_FIX_SIZE) {
        grn_ra *ra = (grn_ra *)obj;
        grn_ra_set_generator(ctx, ra, empty_generator);
      } else {
        grn_ja *ja = (grn_ja *)obj;
        grn_ja_set_generator(ctx, ja, empty_generator);
      }
      grn_obj_unref(ctx, table);
      return ctx->rc;
    }
  }
  grn_obj_unref(ctx, table);
  return ctx->rc;
}

static grn_rc
grn_obj_set_info_generator(grn_ctx *ctx,
                           grn_obj *obj,
                           grn_info_type type,
                           grn_obj *generator,
                           const char *context_tag)
{
  switch (obj->header.type) {
  case GRN_COLUMN_FIX_SIZE:
  case GRN_COLUMN_VAR_SIZE:
    break;
  default:
    ERR(GRN_INVALID_ARGUMENT,
        "%s target object must be one of %s or %s: <%s>",
        context_tag,
        grn_obj_type_to_string(GRN_COLUMN_FIX_SIZE),
        grn_obj_type_to_string(GRN_COLUMN_VAR_SIZE),
        grn_obj_type_to_string(obj->header.type));
    return ctx->rc;
  }

  if (obj->header.domain == GRN_ID_NIL) {
    ERR(GRN_INVALID_ARGUMENT,
        "%s target column must belong to an table",
        context_tag);
    return ctx->rc;
  }

  grn_raw_string generator_string;
  GRN_RAW_STRING_SET(generator_string, generator);
  grn_obj_set_generator(ctx, obj, generator_string, context_tag);
  if (ctx->rc != GRN_SUCCESS) {
    return ctx->rc;
  }

  {
    grn_id id = DB_OBJ(obj)->id;
    grn_log_level log_level =
      (id & GRN_OBJ_TMP_OBJECT) ? GRN_LOG_DEBUG : GRN_LOG_NOTICE;
    GRN_LOG(ctx,
            log_level,
            "DDL:%u:set_generator%s%.*s",
            id,
            GRN_TEXT_LEN(generator) == 0 ? "" : " ",
            (int)GRN_TEXT_LEN(generator),
            GRN_TEXT_VALUE(generator));
  }
  grn_obj_spec_save(ctx, DB_OBJ(obj));

  return GRN_SUCCESS;
}

grn_rc
grn_obj_set_info(grn_ctx *ctx, grn_obj *obj, grn_info_type type, grn_obj *value)
{
  grn_rc rc = GRN_INVALID_ARGUMENT;
  GRN_API_ENTER;
  if (!obj) {
    ERR(GRN_INVALID_ARGUMENT, "grn_obj_set_info failed");
    goto exit;
  }
  grn_obj value_buffer;
  switch (type) {
  case GRN_INFO_SOURCE:
    if (!GRN_DB_OBJP(obj)) {
      ERR(GRN_INVALID_ARGUMENT, "only db_obj can accept GRN_INFO_SOURCE");
      goto exit;
    }
    rc = grn_obj_set_info_source(ctx, obj, value);
    break;
  case GRN_INFO_DEFAULT_TOKENIZER:
    rc = grn_obj_set_info_table_module(ctx,
                                       obj,
                                       type,
                                       value,
                                       "[info][set][default-tokenizer]",
                                       "tokenizer");
    break;
  case GRN_INFO_NORMALIZER:
    rc = grn_obj_set_info_table_module(ctx,
                                       obj,
                                       type,
                                       NULL,
                                       "[info][set][normalizer]",
                                       "normalizer");
    if (rc != GRN_SUCCESS) {
      break;
    }
    type = GRN_INFO_NORMALIZERS;
    if (!grn_obj_is_text_family_bulk(ctx, value)) {
      GRN_PTR_INIT(&value_buffer, GRN_OBJ_VECTOR, GRN_ID_NIL);
      GRN_PTR_PUT(ctx, &value_buffer, value);
      value = &value_buffer;
    }
    /* FALLTHROUGH */
  case GRN_INFO_NORMALIZERS:
    rc = grn_obj_set_info_table_modules(ctx,
                                        obj,
                                        type,
                                        value,
                                        "[info][set][normalizers]",
                                        "normalizers",
                                        "normalizers");
    break;
  case GRN_INFO_TOKEN_FILTERS:
    rc = grn_obj_set_info_table_modules(ctx,
                                        obj,
                                        type,
                                        value,
                                        "[info][set][token-filters]",
                                        "token filters",
                                        "token_filters");
    break;
  case GRN_INFO_GENERATOR:
    rc = grn_obj_set_info_generator(ctx,
                                    obj,
                                    type,
                                    value,
                                    "[info][set][generator]");
    break;
  default:
    /* todo */
    break;
  }
  if (value == &value_buffer) {
    GRN_OBJ_FIN(ctx, &value_buffer);
  }
exit:
  GRN_API_RETURN(rc);
}

grn_obj *
grn_obj_get_element_info(
  grn_ctx *ctx, grn_obj *obj, grn_id id, grn_info_type type, grn_obj *valuebuf)
{
  GRN_API_ENTER;
  GRN_API_RETURN(valuebuf);
}

grn_rc
grn_obj_set_element_info(
  grn_ctx *ctx, grn_obj *obj, grn_id id, grn_info_type type, grn_obj *value)
{
  GRN_API_ENTER;
  GRN_API_RETURN(GRN_SUCCESS);
}

static void
grn_hook_free(grn_ctx *ctx, grn_hook *h)
{
  grn_hook *curr, *next;
  for (curr = h; curr; curr = next) {
    next = curr->next;
    GRN_FREE(curr);
  }
}

grn_rc
grn_obj_add_hook(grn_ctx *ctx,
                 grn_obj *obj,
                 grn_hook_entry entry,
                 int offset,
                 grn_obj *proc,
                 grn_obj *hook_data)
{
  grn_rc rc = GRN_SUCCESS;
  GRN_API_ENTER;
  if (!GRN_DB_OBJP(obj)) {
    rc = GRN_INVALID_ARGUMENT;
  } else {
    int i;
    void *data_value = NULL;
    uint32_t data_size = 0;
    grn_hook *new, **last = &DB_OBJ(obj)->hooks[entry];
    if (hook_data) {
      data_value = GRN_BULK_HEAD(hook_data);
      data_size = GRN_BULK_VSIZE(hook_data);
    }
    if (!(new = GRN_MALLOC(sizeof(grn_hook) + data_size))) {
      rc = GRN_NO_MEMORY_AVAILABLE;
      goto exit;
    }
    new->proc = (grn_proc *)proc;
    new->data_size = data_size;
    if (data_size) {
      grn_memcpy(GRN_NEXT_ADDR(new), data_value, data_size);
    }
    for (i = 0; i != offset && *last; i++) {
      last = &(*last)->next;
    }
    new->next = *last;
    *last = new;
    if (grn_logger_pass(ctx, GRN_LOG_NOTICE)) {
      grn_id id = DB_OBJ(obj)->id;
      uint32_t name_size = 0;
      const char *name = _grn_table_key(ctx, ctx->impl->db, id, &name_size);
      grn_obj extra_info;
      GRN_TEXT_INIT(&extra_info, 0);
      GRN_TEXT_PUTS(ctx, &extra_info, " [");
      grn_hook *hook;
      for (hook = new; hook; hook = hook->next) {
        if (hook != new) {
          GRN_TEXT_PUTC(ctx, &extra_info, ',');
        }
        if (!hook->proc &&
            hook->data_size == sizeof(grn_obj_default_set_value_hook_data)) {
          grn_obj_default_set_value_hook_data *data =
            (grn_obj_default_set_value_hook_data *)GRN_NEXT_ADDR(hook);
          grn_table_get_key2(ctx, ctx->impl->db, data->target, &extra_info);
          grn_text_printf(ctx, &extra_info, "(%u)", data->target);
        } else {
          grn_id hook_proc_id = DB_OBJ(hook->proc)->id;
          grn_table_get_key2(ctx, ctx->impl->db, hook_proc_id, &extra_info);
          grn_text_printf(ctx, &extra_info, "(%u)", hook_proc_id);
        }
      }
      GRN_TEXT_PUTS(ctx, &extra_info, "]");
      GRN_LOG(ctx,
              GRN_LOG_NOTICE,
              "DDL:%u:add_hook:%s%s%.*s%.*s",
              id,
              grn_hook_entry_to_string(entry),
              name_size == 0 ? "" : " ",
              (int)name_size,
              name,
              (int)GRN_TEXT_LEN(&extra_info),
              GRN_TEXT_VALUE(&extra_info));
      GRN_OBJ_FIN(ctx, &extra_info);
    }
    grn_obj_spec_save(ctx, DB_OBJ(obj));
  }
exit:
  GRN_API_RETURN(rc);
}

int
grn_obj_get_nhooks(grn_ctx *ctx, grn_obj *obj, grn_hook_entry entry)
{
  int res = 0;
  GRN_API_ENTER;
  {
    grn_hook *hook = DB_OBJ(obj)->hooks[entry];
    while (hook) {
      res++;
      hook = hook->next;
    }
  }
  GRN_API_RETURN(res);
}

grn_obj *
grn_obj_get_hook(grn_ctx *ctx,
                 grn_obj *obj,
                 grn_hook_entry entry,
                 int offset,
                 grn_obj *data_buf)
{
  grn_obj *res = NULL;
  GRN_API_ENTER;
  {
    int i;
    grn_hook *hook = DB_OBJ(obj)->hooks[entry];
    for (i = 0; i < offset; i++) {
      hook = hook->next;
      if (!hook) {
        return NULL;
      }
    }
    res = (grn_obj *)hook->proc;
    grn_bulk_write(ctx, data_buf, (char *)GRN_NEXT_ADDR(hook), hook->data_size);
  }
  GRN_API_RETURN(res);
}

grn_rc
grn_obj_delete_hook(grn_ctx *ctx,
                    grn_obj *obj,
                    grn_hook_entry entry,
                    int offset)
{
  GRN_API_ENTER;
  grn_obj extra_info;
  GRN_TEXT_INIT(&extra_info, 0);
  bool removed = false;
  {
    int i = 0;
    grn_hook *h, **last = &DB_OBJ(obj)->hooks[entry];
    for (;;) {
      if (!(h = *last)) {
        return GRN_INVALID_ARGUMENT;
      }
      if (++i > offset) {
        removed = true;
        if (!h->proc &&
            h->data_size == sizeof(grn_obj_default_set_value_hook_data)) {
          grn_obj_default_set_value_hook_data *data =
            (grn_obj_default_set_value_hook_data *)GRN_NEXT_ADDR(h);
          GRN_TEXT_PUTC(ctx, &extra_info, ' ');
          grn_table_get_key2(ctx, ctx->impl->db, data->target, &extra_info);
          grn_text_printf(ctx, &extra_info, "(%u)", data->target);
        }
        break;
      }
      last = &h->next;
    }
    *last = h->next;
    GRN_FREE(h);
  }
  if (removed) {
    grn_id id = DB_OBJ(obj)->id;
    uint32_t name_size = 0;
    const char *name = _grn_table_key(ctx, ctx->impl->db, id, &name_size);
    GRN_TEXT_PUTS(ctx, &extra_info, " [");
    grn_hook *first_hook = DB_OBJ(obj)->hooks[entry];
    grn_hook *hook;
    for (hook = first_hook; hook; hook = hook->next) {
      if (hook != first_hook) {
        GRN_TEXT_PUTC(ctx, &extra_info, ',');
      }
      if (!hook->proc &&
          hook->data_size == sizeof(grn_obj_default_set_value_hook_data)) {
        grn_obj_default_set_value_hook_data *data =
          (grn_obj_default_set_value_hook_data *)GRN_NEXT_ADDR(hook);
        grn_table_get_key2(ctx, ctx->impl->db, data->target, &extra_info);
        grn_text_printf(ctx, &extra_info, "(%u)", data->target);
      } else {
        grn_id hook_proc_id = DB_OBJ(hook->proc)->id;
        grn_table_get_key2(ctx, ctx->impl->db, hook_proc_id, &extra_info);
        grn_text_printf(ctx, &extra_info, "(%u)", hook_proc_id);
      }
    }
    GRN_TEXT_PUTS(ctx, &extra_info, "]");
    GRN_LOG(ctx,
            GRN_LOG_NOTICE,
            "DDL:%u:delete_hook:%s%s%.*s%.*s",
            id,
            grn_hook_entry_to_string(entry),
            name_size == 0 ? "" : " ",
            (int)name_size,
            name,
            (int)GRN_TEXT_LEN(&extra_info),
            GRN_TEXT_VALUE(&extra_info));
  }
  GRN_OBJ_FIN(ctx, &extra_info);
  grn_obj_spec_save(ctx, DB_OBJ(obj));
  GRN_API_RETURN(GRN_SUCCESS);
}

static grn_rc
remove_index(grn_ctx *ctx, grn_obj *obj, grn_hook_entry entry, uint32_t flags)
{
  const char *tag = "[object][remove][index]";
  grn_rc rc = GRN_SUCCESS;
  grn_hook *hooks = DB_OBJ(obj)->hooks[entry];
  DB_OBJ(obj)->hooks[entry] = NULL; /* avoid mutual recursive call */
  if (!hooks) {
    return rc;
  }
  GRN_DEFINE_NAME(obj);
  while (hooks) {
    grn_obj_default_set_value_hook_data *data = (void *)GRN_NEXT_ADDR(hooks);
    grn_obj *target = grn_ctx_at(ctx, data->target);
    if (!target) {
      char hook_name[GRN_TABLE_MAX_KEY_SIZE];
      int hook_name_length;

      hook_name_length = grn_table_get_key(ctx,
                                           ctx->impl->db,
                                           data->target,
                                           hook_name,
                                           GRN_TABLE_MAX_KEY_SIZE);
      ERR(GRN_OBJECT_CORRUPT,
          "%s[%s][%s] hook has a dangling reference: <%.*s>(%u)",
          tag,
          name,
          grn_hook_entry_to_string(entry),
          hook_name_length,
          hook_name,
          data->target);
      if (flags & GRN_OBJ_REMOVE_ENSURE) {
        ERRCLR(ctx);
        if (data->target != GRN_ID_NIL) {
          grn_ctx_remove_by_id(ctx, data->target, flags);
        }
      }
      rc = ctx->rc;
    } else if (target->header.type == GRN_COLUMN_INDEX) {
      // TODO: multicolumn  MULTI_COLUMN_INDEXP
      rc = grn_obj_remove_internal(ctx, target, flags);
    } else {
      grn_obj inspected;
      GRN_TEXT_INIT(&inspected, 0);
      grn_inspect_limited(ctx, &inspected, target);
      ERR(GRN_UNKNOWN_ERROR,
          "%s[%s][%s] hook has an unsupported index target: %u: %.*s",
          tag,
          name,
          grn_hook_entry_to_string(entry),
          data->target,
          (int)GRN_TEXT_LEN(&inspected),
          GRN_TEXT_VALUE(&inspected));
      GRN_OBJ_FIN(ctx, &inspected);
      rc = ctx->rc;
    }
    if (rc != GRN_SUCCESS) {
      DB_OBJ(obj)->hooks[entry] = hooks;
      break;
    }
    grn_hook *current_hook = hooks;
    hooks = hooks->next;
    GRN_FREE(current_hook);
  }
  return rc;
}

static grn_rc
grn_ctx_remove_by_id_internal(grn_ctx *ctx,
                              grn_id id,
                              uint32_t flags,
                              bool is_top_level);

/* This should be used only when the target object can't be opened. If
 * the target object can be opened, use remove_index() instead. */
static grn_rc
remove_index_full_scan(grn_ctx *ctx, grn_id target_id, uint32_t flags)
{
  GRN_DB_EACH_SPEC_BEGIN(ctx, cursor, id, spec)
  {
    if (id == target_id) {
      continue;
    }
    if (grn_obj_type_is_column(spec->header.type)) {
      /* TODO: We should not access to internal variable in
       * GRN_DB_EACH_SPEC_BEGIN(). */
      const char *raw_source_ids;
      uint32_t size = grn_vector_get_element(ctx,
                                             &decoded_spec,
                                             GRN_SERIALIZED_SPEC_INDEX_SOURCE,
                                             &raw_source_ids,
                                             NULL,
                                             NULL);
      if (size > 0) {
        grn_id *source_ids = (grn_id *)raw_source_ids;
        size_t n_ids = size / sizeof(grn_id);
        size_t i;
        for (i = 0; i < n_ids; i++) {
          grn_id source_id = source_ids[i];
          if (source_id == target_id) {
            grn_ctx_remove_by_id_internal(ctx, id, flags, false);
            break;
          }
        }
      }
      if (ctx->rc != GRN_SUCCESS) {
        break;
      }
    }
  }
  GRN_DB_EACH_SPEC_END(ctx, cursor);
  return ctx->rc;
}

static grn_rc
remove_columns_raw(grn_ctx *ctx,
                   grn_id table_id,
                   const char *table_name,
                   uint32_t table_name_size,
                   uint32_t flags)
{
  const char *tag = "[table][remove][columns]";
  grn_rc rc = GRN_SUCCESS;

  char prefix[GRN_TABLE_MAX_KEY_SIZE];
  grn_strncpy(prefix, GRN_TABLE_MAX_KEY_SIZE, table_name, table_name_size);
  prefix[table_name_size] = GRN_DB_DELIMITER;
  GRN_TABLE_EACH_BEGIN_MIN(ctx,
                           ctx->impl->db,
                           cursor,
                           column_id,
                           prefix,
                           table_name_size + 1 /* GRN_DB_DELIMITER */,
                           GRN_CURSOR_PREFIX)
  {
    grn_obj *column = grn_ctx_at(ctx, column_id);
    if (column) {
      rc = grn_obj_remove_internal(ctx, column, flags);
      if (rc != GRN_SUCCESS) {
        grn_obj_unlink(ctx, column);
        break;
      }
    } else {
      uint32_t column_name_size;
      const char *column_name =
        _grn_table_key(ctx, ctx->impl->db, column_id, &column_name_size);
      if (ctx->rc == GRN_SUCCESS) {
        ERR(GRN_INVALID_ARGUMENT,
            "%s[%.*s] column is broken: <%.*s>(%u)",
            tag,
            (int)table_name_size,
            table_name,
            column_name_size,
            column_name,
            column_id);
      } else {
        char errbuf[GRN_CTX_MSGSIZE];
        grn_strcpy(errbuf, GRN_CTX_MSGSIZE, ctx->errbuf);
        ERR(ctx->rc,
            "%s[%.*s] column is broken: <%.*s>(%u): %s",
            tag,
            (int)table_name_size,
            table_name,
            column_name_size,
            column_name,
            column_id,
            errbuf);
      }
      if (flags & GRN_OBJ_REMOVE_ENSURE) {
        ERRCLR(ctx);
        grn_ctx_remove_by_id(ctx, column_id, flags);
      }
      rc = ctx->rc;
      if (rc != GRN_SUCCESS) {
        break;
      }
    }
  }
  GRN_TABLE_EACH_END(ctx, cursor);

  return rc;
}

static grn_rc
remove_columns(grn_ctx *ctx, grn_obj *table, uint32_t flags)
{
  grn_id table_id = DB_OBJ(table)->id;
  uint32_t table_name_size;
  const char *table_name =
    _grn_table_key(ctx, ctx->impl->db, table_id, &table_name_size);
  return remove_columns_raw(ctx, table_id, table_name, table_name_size, flags);
}

static grn_rc
grn_obj_remove_db_index_columns(grn_ctx *ctx, grn_obj *db)
{
  grn_rc rc = GRN_SUCCESS;
  grn_table_cursor *cur;
  if ((cur = grn_table_cursor_open(ctx, db, NULL, 0, NULL, 0, 0, -1, 0))) {
    grn_id id;
    while ((id = grn_table_cursor_next_inline(ctx, cur)) != GRN_ID_NIL) {
      grn_obj *obj = grn_ctx_at(ctx, id);
      if (obj && obj->header.type == GRN_COLUMN_INDEX) {
        rc = grn_obj_remove_internal(ctx, obj, 0);
        if (rc != GRN_SUCCESS) {
          grn_obj_unlink(ctx, obj);
          break;
        }
      }
    }
    grn_table_cursor_close(ctx, cur);
  }
  return rc;
}

static grn_rc
grn_obj_remove_db_reference_columns(grn_ctx *ctx, grn_obj *db)
{
  grn_rc rc = GRN_SUCCESS;
  grn_table_cursor *cur;
  if ((cur = grn_table_cursor_open(ctx, db, NULL, 0, NULL, 0, 0, -1, 0))) {
    grn_id id;
    while ((id = grn_table_cursor_next_inline(ctx, cur)) != GRN_ID_NIL) {
      grn_obj *obj = grn_ctx_at(ctx, id);
      grn_obj *range = NULL;

      if (!obj) {
        continue;
      }

      switch (obj->header.type) {
      case GRN_COLUMN_FIX_SIZE:
      case GRN_COLUMN_VAR_SIZE:
        if (!DB_OBJ(obj)->range) {
          break;
        }

        range = grn_ctx_at(ctx, DB_OBJ(obj)->range);
        if (!range) {
          break;
        }

        switch (range->header.type) {
        case GRN_TABLE_NO_KEY:
        case GRN_TABLE_HASH_KEY:
        case GRN_TABLE_PAT_KEY:
        case GRN_TABLE_DAT_KEY:
          rc = grn_obj_remove_internal(ctx, obj, 0);
          break;
        }
        break;
      }

      if (rc != GRN_SUCCESS) {
        break;
      }
    }
    grn_table_cursor_close(ctx, cur);
  }
  return rc;
}

static grn_rc
grn_obj_remove_db_reference_tables(grn_ctx *ctx, grn_obj *db)
{
  grn_rc rc = GRN_SUCCESS;
  grn_table_cursor *cur;
  if ((cur = grn_table_cursor_open(ctx, db, NULL, 0, NULL, 0, 0, -1, 0))) {
    grn_id id;
    while ((id = grn_table_cursor_next_inline(ctx, cur)) != GRN_ID_NIL) {
      grn_obj *obj = grn_ctx_at(ctx, id);
      grn_obj *domain = NULL;

      if (!obj) {
        continue;
      }

      switch (obj->header.type) {
      case GRN_TABLE_HASH_KEY:
      case GRN_TABLE_PAT_KEY:
      case GRN_TABLE_DAT_KEY:
        if (!obj->header.domain) {
          break;
        }

        domain = grn_ctx_at(ctx, obj->header.domain);
        if (!domain) {
          break;
        }

        switch (domain->header.type) {
        case GRN_TABLE_NO_KEY:
        case GRN_TABLE_HASH_KEY:
        case GRN_TABLE_PAT_KEY:
        case GRN_TABLE_DAT_KEY:
          rc = grn_obj_remove_internal(ctx, obj, 0);
          break;
        }
        break;
      }

      if (rc != GRN_SUCCESS) {
        break;
      }
    }
    grn_table_cursor_close(ctx, cur);
  }
  return rc;
}

static grn_rc
grn_obj_remove_db_all_tables(grn_ctx *ctx, grn_obj *db)
{
  grn_rc rc = GRN_SUCCESS;
  grn_table_cursor *cur;
  if ((cur = grn_table_cursor_open(ctx, db, NULL, 0, NULL, 0, 0, -1, 0))) {
    grn_id id;
    while ((id = grn_table_cursor_next_inline(ctx, cur)) != GRN_ID_NIL) {
      grn_obj *obj = grn_ctx_at(ctx, id);

      if (!obj) {
        continue;
      }

      switch (obj->header.type) {
      case GRN_TABLE_NO_KEY:
      case GRN_TABLE_HASH_KEY:
      case GRN_TABLE_PAT_KEY:
      case GRN_TABLE_DAT_KEY:
        rc = grn_obj_remove_internal(ctx, obj, 0);
        break;
      }

      if (rc != GRN_SUCCESS) {
        break;
      }
    }
    grn_table_cursor_close(ctx, cur);
  }
  return rc;
}

static grn_rc
grn_obj_remove_db(
  grn_ctx *ctx, grn_obj *obj, grn_obj *db, grn_id id, const char *path)
{
  grn_rc rc = GRN_SUCCESS;
  const char *io_spath;
  char *spath;
  grn_db *s = (grn_db *)db;
  unsigned char key_type;

  rc = grn_obj_remove_db_index_columns(ctx, db);
  if (rc != GRN_SUCCESS) {
    return rc;
  }
  rc = grn_obj_remove_db_reference_columns(ctx, db);
  if (rc != GRN_SUCCESS) {
    return rc;
  }
  rc = grn_obj_remove_db_reference_tables(ctx, db);
  if (rc != GRN_SUCCESS) {
    return rc;
  }
  rc = grn_obj_remove_db_all_tables(ctx, db);
  if (rc != GRN_SUCCESS) {
    return rc;
  }

  if (s->specs && (io_spath = grn_obj_path(ctx, (grn_obj *)s->specs)) &&
      *io_spath != '\0') {
    if (!(spath = GRN_STRDUP(io_spath))) {
      ERR(GRN_NO_MEMORY_AVAILABLE, "cannot duplicate path: <%s>", io_spath);
      return ctx->rc;
    }
  } else {
    spath = NULL;
  }

  key_type = s->keys->header.type;

  rc = grn_obj_close(ctx, obj);
  if (rc != GRN_SUCCESS) {
    if (spath) {
      GRN_FREE(spath);
    }
    return rc;
  }

  if (spath) {
    rc = grn_ja_remove(ctx, spath);
    GRN_FREE(spath);
    if (rc != GRN_SUCCESS) {
      return rc;
    }
  }

  if (path) {
    switch (key_type) {
    case GRN_TABLE_PAT_KEY:
      rc = grn_pat_remove(ctx, path);
      break;
    case GRN_TABLE_DAT_KEY:
      rc = grn_dat_remove(ctx, path);
      break;
    }
    if (rc == GRN_SUCCESS) {
      rc = grn_db_config_remove(ctx, path);
    } else {
      grn_db_config_remove(ctx, path);
    }
    if (rc == GRN_SUCCESS) {
      rc = grn_options_remove(ctx, path);
    } else {
      grn_options_remove(ctx, path);
    }
  }

  return rc;
}

static grn_rc
remove_reference_tables_raw(grn_ctx *ctx,
                            grn_id table_id,
                            const char *table_name,
                            uint32_t table_name_size,
                            grn_obj *db,
                            uint32_t flags)
{
  grn_rc rc = GRN_SUCCESS;
  grn_bool is_close_opened_object_mode = GRN_FALSE;
  grn_table_cursor *cursor;

  if (grn_thread_get_limit() == 1) {
    is_close_opened_object_mode = GRN_TRUE;
  }

  if ((cursor = grn_table_cursor_open(ctx,
                                      db,
                                      NULL,
                                      0,
                                      NULL,
                                      0,
                                      0,
                                      -1,
                                      GRN_CURSOR_BY_ID))) {
    grn_id id;
    while ((id = grn_table_cursor_next(ctx, cursor)) != GRN_ID_NIL) {
      grn_obj *object;
      bool is_removed = false;

      if (is_close_opened_object_mode) {
        grn_ctx_push_temporary_open_space(ctx);
      }

      object = grn_ctx_at(ctx, id);
      if (!object) {
        ERRCLR(ctx);
        if (is_close_opened_object_mode) {
          grn_ctx_pop_temporary_open_space(ctx);
        }
        continue;
      }

      switch (object->header.type) {
      case GRN_TABLE_HASH_KEY:
      case GRN_TABLE_PAT_KEY:
      case GRN_TABLE_DAT_KEY:
        if (DB_OBJ(object)->id == table_id) {
          break;
        }

        if (object->header.domain == table_id) {
          rc = grn_obj_remove_internal(ctx, object, flags);
          is_removed = (grn_table_at(ctx, db, id) == GRN_ID_NIL);
        }
        break;
      case GRN_TABLE_NO_KEY:
        break;
      case GRN_COLUMN_VAR_SIZE:
      case GRN_COLUMN_FIX_SIZE:
        if (object->header.domain == table_id) {
          break;
        }
        if (DB_OBJ(object)->range == table_id) {
          rc = grn_obj_remove_internal(ctx, object, flags);
          is_removed = (grn_table_at(ctx, db, id) == GRN_ID_NIL);
        }
        break;
      case GRN_COLUMN_INDEX:
        break;
      default:
        break;
      }

      if (is_close_opened_object_mode) {
        grn_ctx_pop_temporary_open_space(ctx);
      } else {
        if (!is_removed) {
          grn_obj_unlink(ctx, object);
        }
      }

      if (rc != GRN_SUCCESS) {
        break;
      }
    }
    grn_table_cursor_close(ctx, cursor);
  }

  return rc;
}

static grn_rc
remove_reference_tables(grn_ctx *ctx,
                        grn_obj *table,
                        grn_obj *db,
                        uint32_t flags)
{
  grn_id table_id = DB_OBJ(table)->id;
  uint32_t table_name_size;
  const char *table_name = _grn_table_key(ctx, db, table_id, &table_name_size);
  return remove_reference_tables_raw(ctx,
                                     table_id,
                                     table_name,
                                     table_name_size,
                                     db,
                                     flags);
}

static bool
is_removable_table_raw(grn_ctx *ctx,
                       grn_id table_id,
                       const char *table_name,
                       uint32_t table_name_size,
                       grn_obj *db)
{
  grn_id reference_object_id;

  if (table_id & GRN_OBJ_TMP_OBJECT) {
    return true;
  }

  reference_object_id = grn_table_find_reference_object_raw(ctx, table_id);
  if (reference_object_id == GRN_ID_NIL) {
    return true;
  }

  {
    grn_obj *db;
    grn_obj *reference_object;
    const char *reference_object_name;
    int reference_object_name_size;

    db = grn_ctx_db(ctx);

    reference_object = grn_ctx_at(ctx, reference_object_id);
    reference_object_name =
      _grn_table_key(ctx, db, reference_object_id, &reference_object_name_size);
    if (reference_object) {
      if (grn_obj_is_table(ctx, reference_object)) {
        ERR(GRN_OPERATION_NOT_PERMITTED,
            "[table][remove] a table that references the table exists: "
            "<%.*s._key> -> <%.*s>",
            reference_object_name_size,
            reference_object_name,
            table_name_size,
            table_name);
      } else {
        ERR(GRN_OPERATION_NOT_PERMITTED,
            "[table][remove] a column that references the table exists: "
            "<%.*s> -> <%.*s>",
            reference_object_name_size,
            reference_object_name,
            table_name_size,
            table_name);
      }
    } else {
      ERR(GRN_OPERATION_NOT_PERMITTED,
          "[table][remove] a dangling object that references the table exists: "
          "<%.*s(%u)> -> <%.*s>",
          reference_object_name_size,
          reference_object_name,
          reference_object_id,
          table_name_size,
          table_name);
    }
  }

  return false;
}

static bool
is_removable_table(grn_ctx *ctx, grn_obj *table, grn_obj *db)
{
  grn_id table_id = DB_OBJ(table)->id;
  const char *table_name;
  int table_name_size;
  table_name = _grn_table_key(ctx, db, table_id, &table_name_size);
  return is_removable_table_raw(ctx, table_id, table_name, table_name_size, db);
}

static inline void
grn_obj_remove_log_spec_remove(grn_ctx *ctx,
                               grn_obj *db,
                               grn_id id,
                               uint8_t type)
{
  const char *name;
  uint32_t name_size = 0;

  name = _grn_table_key(ctx, db, id, &name_size);
  /* TODO: reduce log level. */
  GRN_LOG(ctx,
          GRN_LOG_NOTICE,
          "spec:%u:remove:%.*s:%u(%s)",
          id,
          name_size,
          name,
          type,
          grn_obj_type_to_string(type));
}

static void
grn_ctx_generate_removing_path(grn_ctx *ctx,
                               grn_id id,
                               char *path,
                               size_t path_size)
{
  const char *suffix = ".removing";
  grn_obj_path_by_id(ctx, ctx->impl->db, id, path);
  grn_strcat(path, path_size, suffix);
}

static void
grn_ctx_mark_removing(grn_ctx *ctx, grn_id id)
{
  char path[PATH_MAX];
  grn_ctx_generate_removing_path(ctx, id, path, PATH_MAX);
  FILE *removing = grn_fopen(path, "w");
  if (removing) {
    fclose(removing);
  }
}

bool
grn_ctx_is_removing(grn_ctx *ctx, grn_id id)
{
  char path[PATH_MAX];
  grn_ctx_generate_removing_path(ctx, id, path, PATH_MAX);
  struct stat s;
  return stat(path, &s) == 0;
}

static void
grn_ctx_done_removing(grn_ctx *ctx, grn_id id)
{
  char path[PATH_MAX];
  grn_ctx_generate_removing_path(ctx, id, path, PATH_MAX);
  grn_unlink(path);
}

static grn_rc
grn_obj_remove_pat(grn_ctx *ctx,
                   grn_obj *obj,
                   grn_obj *db,
                   grn_id id,
                   const char *path,
                   uint32_t flags)
{
  grn_rc rc = GRN_SUCCESS;
  uint8_t type;

  type = obj->header.type;

  if (flags & GRN_OBJ_REMOVE_DEPENDENT) {
    rc = remove_reference_tables(ctx, obj, db, flags);
    if (rc != GRN_SUCCESS) {
      return rc;
    }
  } else {
    if (!is_removable_table(ctx, obj, db)) {
      return ctx->rc;
    }
  }

  rc = remove_index(ctx, obj, GRN_HOOK_INSERT, flags);
  if (rc != GRN_SUCCESS) {
    return rc;
  }
  rc = remove_columns(ctx, obj, flags);
  if (rc != GRN_SUCCESS) {
    return rc;
  }

  rc = grn_obj_close(ctx, obj);
  if (rc != GRN_SUCCESS) {
    return rc;
  }

  if (path) {
    grn_ctx_mark_removing(ctx, id);
    rc = grn_pat_remove(ctx, path);
    if (rc != GRN_SUCCESS) {
      return rc;
    }
    grn_obj_remove_log_spec_remove(ctx, db, id, type);
    rc = grn_obj_delete_by_id(ctx, db, id, GRN_TRUE);
    if (rc != GRN_SUCCESS) {
      return rc;
    }
    grn_ctx_done_removing(ctx, id);
  }

  if (!(id & GRN_OBJ_TMP_OBJECT)) {
    grn_obj_touch(ctx, db, NULL);
  }

  return rc;
}

static grn_rc
grn_obj_remove_dat(grn_ctx *ctx,
                   grn_obj *obj,
                   grn_obj *db,
                   grn_id id,
                   const char *path,
                   uint32_t flags)
{
  grn_rc rc = GRN_SUCCESS;
  uint8_t type;

  type = obj->header.type;

  if (flags & GRN_OBJ_REMOVE_DEPENDENT) {
    rc = remove_reference_tables(ctx, obj, db, flags);
    if (rc != GRN_SUCCESS) {
      return rc;
    }
  } else {
    if (!is_removable_table(ctx, obj, db)) {
      return ctx->rc;
    }
  }

  rc = remove_index(ctx, obj, GRN_HOOK_INSERT, flags);
  if (rc != GRN_SUCCESS) {
    return rc;
  }
  rc = remove_columns(ctx, obj, flags);
  if (rc != GRN_SUCCESS) {
    return rc;
  }

  rc = grn_obj_close(ctx, obj);
  if (rc != GRN_SUCCESS) {
    return rc;
  }

  if (path) {
    grn_ctx_mark_removing(ctx, id);
    rc = grn_dat_remove(ctx, path);
    if (rc != GRN_SUCCESS) {
      return rc;
    }
    grn_obj_remove_log_spec_remove(ctx, db, id, type);
    rc = grn_obj_delete_by_id(ctx, db, id, GRN_TRUE);
    if (rc != GRN_SUCCESS) {
      return rc;
    }
    grn_ctx_done_removing(ctx, id);
  }

  if (!(id & GRN_OBJ_TMP_OBJECT)) {
    grn_obj_touch(ctx, db, NULL);
  }

  return rc;
}

static grn_rc
grn_obj_remove_hash(grn_ctx *ctx,
                    grn_obj *obj,
                    grn_obj *db,
                    grn_id id,
                    const char *path,
                    uint32_t flags)
{
  grn_rc rc = GRN_SUCCESS;
  uint8_t type;

  type = obj->header.type;

  if (flags & GRN_OBJ_REMOVE_DEPENDENT) {
    rc = remove_reference_tables(ctx, obj, db, flags);
    if (rc != GRN_SUCCESS) {
      return rc;
    }
  } else {
    if (!is_removable_table(ctx, obj, db)) {
      return ctx->rc;
    }
  }

  rc = remove_index(ctx, obj, GRN_HOOK_INSERT, flags);
  if (rc != GRN_SUCCESS) {
    return rc;
  }
  rc = remove_columns(ctx, obj, flags);
  if (rc != GRN_SUCCESS) {
    return rc;
  }

  rc = grn_obj_close(ctx, obj);
  if (rc != GRN_SUCCESS) {
    return rc;
  }

  if (path) {
    grn_ctx_mark_removing(ctx, id);
    rc = grn_hash_remove(ctx, path);
    if (rc != GRN_SUCCESS) {
      return rc;
    }
    grn_obj_remove_log_spec_remove(ctx, db, id, type);
    rc = grn_obj_delete_by_id(ctx, db, id, GRN_TRUE);
    if (rc != GRN_SUCCESS) {
      return rc;
    }
    grn_ctx_done_removing(ctx, id);
  }

  if (!(id & GRN_OBJ_TMP_OBJECT)) {
    grn_obj_touch(ctx, db, NULL);
  }

  return rc;
}

static grn_rc
grn_obj_remove_array(grn_ctx *ctx,
                     grn_obj *obj,
                     grn_obj *db,
                     grn_id id,
                     const char *path,
                     uint32_t flags)
{
  grn_rc rc = GRN_SUCCESS;
  uint8_t type;

  type = obj->header.type;

  if (flags & GRN_OBJ_REMOVE_DEPENDENT) {
    rc = remove_reference_tables(ctx, obj, db, flags);
    if (rc != GRN_SUCCESS) {
      return rc;
    }
  } else {
    if (!is_removable_table(ctx, obj, db)) {
      return ctx->rc;
    }
  }

  rc = remove_columns(ctx, obj, flags);
  if (rc != GRN_SUCCESS) {
    return rc;
  }

  rc = grn_obj_close(ctx, obj);
  if (rc != GRN_SUCCESS) {
    return rc;
  }

  if (path) {
    grn_ctx_mark_removing(ctx, id);
    rc = grn_array_remove(ctx, path);
    if (rc != GRN_SUCCESS) {
      return rc;
    }
    grn_obj_remove_log_spec_remove(ctx, db, id, type);
    rc = grn_obj_delete_by_id(ctx, db, id, GRN_TRUE);
    if (rc != GRN_SUCCESS) {
      return rc;
    }
    grn_ctx_done_removing(ctx, id);
  }

  if (!(id & GRN_OBJ_TMP_OBJECT)) {
    grn_obj_touch(ctx, db, NULL);
  }

  return rc;
}

static grn_rc
grn_obj_remove_ja(grn_ctx *ctx,
                  grn_obj *obj,
                  grn_obj *db,
                  grn_id id,
                  const char *path,
                  uint32_t flags)
{
  grn_rc rc = GRN_SUCCESS;
  uint8_t type;

  type = obj->header.type;

  delete_source_hook(ctx, obj);
  rc = remove_index(ctx, obj, GRN_HOOK_SET, flags);
  if (rc != GRN_SUCCESS) {
    return rc;
  }
  rc = grn_obj_close(ctx, obj);
  if (rc != GRN_SUCCESS) {
    return rc;
  }

  if (path) {
    grn_ctx_mark_removing(ctx, id);
    rc = grn_ja_remove(ctx, path);
    if (rc != GRN_SUCCESS) {
      return rc;
    }
    grn_obj_remove_log_spec_remove(ctx, db, id, type);
    rc = grn_obj_delete_by_id(ctx, db, id, GRN_TRUE);
    if (rc != GRN_SUCCESS) {
      return rc;
    }
    grn_ctx_done_removing(ctx, id);
  }

  if (!(id & GRN_OBJ_TMP_OBJECT)) {
    grn_obj_touch(ctx, db, NULL);
  }

  return rc;
}

static grn_rc
grn_obj_remove_ra(grn_ctx *ctx,
                  grn_obj *obj,
                  grn_obj *db,
                  grn_id id,
                  const char *path,
                  uint32_t flags)
{
  grn_rc rc = GRN_SUCCESS;
  uint8_t type;

  type = obj->header.type;

  rc = remove_index(ctx, obj, GRN_HOOK_SET, flags);
  if (rc != GRN_SUCCESS) {
    return rc;
  }
  rc = grn_obj_close(ctx, obj);
  if (rc != GRN_SUCCESS) {
    return rc;
  }

  if (path) {
    grn_ctx_mark_removing(ctx, id);
    rc = grn_ra_remove(ctx, path);
    if (rc != GRN_SUCCESS) {
      return rc;
    }
    grn_obj_remove_log_spec_remove(ctx, db, id, type);
    rc = grn_obj_delete_by_id(ctx, db, id, GRN_TRUE);
    if (rc != GRN_SUCCESS) {
      return rc;
    }
    grn_ctx_done_removing(ctx, id);
  }

  if (!(id & GRN_OBJ_TMP_OBJECT)) {
    grn_obj_touch(ctx, db, NULL);
  }

  return rc;
}

static grn_rc
grn_obj_remove_index(grn_ctx *ctx,
                     grn_obj *obj,
                     grn_obj *db,
                     grn_id id,
                     const char *path,
                     uint32_t flags)
{
  grn_rc rc = GRN_SUCCESS;
  uint8_t type;

  type = obj->header.type;

  delete_source_hook(ctx, obj);
  rc = grn_obj_close(ctx, obj);
  if (rc != GRN_SUCCESS) {
    return rc;
  }

  if (path) {
    grn_ctx_mark_removing(ctx, id);
    rc = grn_ii_remove(ctx, path);
    if (rc != GRN_SUCCESS) {
      return rc;
    }
    grn_obj_remove_log_spec_remove(ctx, db, id, type);
    rc = grn_obj_delete_by_id(ctx, db, id, GRN_TRUE);
    if (rc != GRN_SUCCESS) {
      return rc;
    }
    grn_ctx_done_removing(ctx, id);
  }

  if (!(id & GRN_OBJ_TMP_OBJECT)) {
    grn_obj_touch(ctx, db, NULL);
  }

  return rc;
}

static grn_rc
grn_obj_remove_db_obj(
  grn_ctx *ctx, grn_obj *obj, grn_obj *db, grn_id id, const char *path)
{
  grn_rc rc = GRN_SUCCESS;
  uint8_t type;

  type = obj->header.type;

  rc = grn_obj_close(ctx, obj);
  if (rc != GRN_SUCCESS) {
    return rc;
  }

  if (path) {
    grn_ctx_mark_removing(ctx, id);
    rc = grn_io_remove(ctx, path);
    if (rc != GRN_SUCCESS) {
      return rc;
    }
  }

  if (!(id & GRN_OBJ_TMP_OBJECT)) {
    grn_obj_remove_log_spec_remove(ctx, db, id, type);
    rc = grn_obj_delete_by_id(ctx, db, id, GRN_TRUE);
    if (rc != GRN_SUCCESS) {
      return rc;
    }
    grn_obj_touch(ctx, db, NULL);
  }

  if (path) {
    grn_ctx_done_removing(ctx, id);
  }

  return rc;
}

static grn_rc
grn_obj_remove_other(
  grn_ctx *ctx, grn_obj *obj, grn_obj *db, grn_id id, const char *path)
{
  return grn_obj_close(ctx, obj);
}

static grn_rc
grn_obj_remove_internal(grn_ctx *ctx, grn_obj *obj, uint32_t flags)
{
  grn_rc rc = GRN_SUCCESS;
  grn_id id = GRN_ID_NIL;
  grn_obj *db = NULL;
  const char *io_path;
  char *path;
  grn_bool is_temporary_open_target = GRN_FALSE;

  if (ctx->impl && ctx->impl->db) {
    grn_id id;
    uint32_t s = 0;
    const char *n;

    id = DB_OBJ(obj)->id;
    n = _grn_table_key(ctx, ctx->impl->db, id, &s);
    if (s > 0) {
      GRN_LOG(ctx, GRN_LOG_NOTICE, "DDL:%u:obj_remove %.*s", id, s, n);
    }
  }
  if (obj->header.type != GRN_PROC && (io_path = grn_obj_path(ctx, obj)) &&
      *io_path != '\0') {
    if (!(path = GRN_STRDUP(io_path))) {
      ERR(GRN_NO_MEMORY_AVAILABLE, "cannot duplicate path: <%s>", io_path);
      return ctx->rc;
    }
  } else {
    path = NULL;
  }
  if (GRN_DB_OBJP(obj)) {
    id = DB_OBJ(obj)->id;
    db = DB_OBJ(obj)->db;
    rc = grn_obj_clear_option_values(ctx, obj);
  }
  switch (obj->header.type) {
  case GRN_DB:
    rc = grn_obj_remove_db(ctx, obj, db, id, path);
    break;
  case GRN_TABLE_PAT_KEY:
    grn_ctx_impl_columns_cache_delete(ctx, id);
    rc = grn_obj_remove_pat(ctx, obj, db, id, path, flags);
    is_temporary_open_target = GRN_TRUE;
    break;
  case GRN_TABLE_DAT_KEY:
    grn_ctx_impl_columns_cache_delete(ctx, id);
    rc = grn_obj_remove_dat(ctx, obj, db, id, path, flags);
    is_temporary_open_target = GRN_TRUE;
    break;
  case GRN_TABLE_HASH_KEY:
    grn_ctx_impl_columns_cache_delete(ctx, id);
    rc = grn_obj_remove_hash(ctx, obj, db, id, path, flags);
    is_temporary_open_target = GRN_TRUE;
    break;
  case GRN_TABLE_NO_KEY:
    grn_ctx_impl_columns_cache_delete(ctx, id);
    rc = grn_obj_remove_array(ctx, obj, db, id, path, flags);
    is_temporary_open_target = GRN_TRUE;
    break;
  case GRN_COLUMN_VAR_SIZE:
    grn_ctx_impl_columns_cache_delete(ctx, obj->header.domain);
    rc = grn_obj_remove_ja(ctx, obj, db, id, path, flags);
    is_temporary_open_target = GRN_TRUE;
    break;
  case GRN_COLUMN_FIX_SIZE:
    grn_ctx_impl_columns_cache_delete(ctx, obj->header.domain);
    rc = grn_obj_remove_ra(ctx, obj, db, id, path, flags);
    is_temporary_open_target = GRN_TRUE;
    break;
  case GRN_COLUMN_INDEX:
    grn_ctx_impl_columns_cache_delete(ctx, obj->header.domain);
    rc = grn_obj_remove_index(ctx, obj, db, id, path, flags);
    is_temporary_open_target = GRN_TRUE;
    break;
  default:
    if (GRN_DB_OBJP(obj)) {
      rc = grn_obj_remove_db_obj(ctx, obj, db, id, path);
    } else {
      rc = grn_obj_remove_other(ctx, obj, db, id, path);
    }
  }
  if (path) {
    GRN_FREE(path);
  } else {
    is_temporary_open_target = GRN_FALSE;
  }

  if (is_temporary_open_target && rc == GRN_SUCCESS) {
    grn_obj *space;
    space = ctx->impl->temporary_open_spaces.current;
    if (space) {
      unsigned int i, n_elements;
      n_elements = GRN_PTR_VECTOR_SIZE(space);
      for (i = 0; i < n_elements; i++) {
        if (GRN_PTR_VALUE_AT(space, i) == obj) {
          GRN_PTR_VALUE_AT(space, i) = NULL;
        }
      }
    }
  }

  return rc;
}

grn_rc
grn_obj_remove(grn_ctx *ctx, grn_obj *obj)
{
  return grn_obj_remove_flags(ctx, obj, 0);
}

grn_rc
grn_obj_remove_dependent(grn_ctx *ctx, grn_obj *obj)
{
  return grn_obj_remove_flags(ctx, obj, GRN_OBJ_REMOVE_DEPENDENT);
}

grn_rc
grn_obj_remove_flags(grn_ctx *ctx, grn_obj *obj, uint32_t flags)
{
  grn_rc rc = GRN_SUCCESS;
  GRN_API_ENTER;
  if (ctx->impl && ctx->impl->db && ctx->impl->db != obj) {
    grn_io *io = grn_obj_get_io(ctx, ctx->impl->db);
    rc = grn_io_lock(ctx, io, grn_lock_timeout);
    if (rc == GRN_SUCCESS) {
      rc = grn_obj_remove_internal(ctx, obj, flags);
      grn_io_unlock(ctx, io);
    }
  } else {
    rc = grn_obj_remove_internal(ctx, obj, flags);
  }
  GRN_API_RETURN(rc);
}

grn_rc
grn_obj_remove_force(grn_ctx *ctx, const char *name, int name_size)
{
  grn_obj *db;

  GRN_API_ENTER;

  if (!(ctx->impl && ctx->impl->db)) {
    ERR(GRN_INVALID_ARGUMENT,
        "[object][remove][force] database isn't initialized");
    GRN_API_RETURN(ctx->rc);
  }

  db = ctx->impl->db;
  if (name_size == -1) {
    name_size = strlen(name);
  }
  grn_id id = grn_table_get(ctx, db, name, name_size);
  if (id == GRN_ID_NIL) {
    ERR(GRN_INVALID_ARGUMENT,
        "[object][remove][force] nonexistent object: <%.*s>",
        name_size,
        name);
    GRN_API_RETURN(ctx->rc);
  }

  grn_obj_delete_by_id(ctx, db, id, true);
  {
    char path[PATH_MAX];
    grn_obj_path_by_id(ctx, db, id, path);
    grn_io_remove_if_exist(ctx, path);
    grn_strcat(path, PATH_MAX, ".c");
    grn_io_remove_if_exist(ctx, path);
  }

  GRN_API_RETURN(ctx->rc);
}

static uint8_t
grn_ctx_get_type(grn_ctx *ctx, grn_id id)
{
  grn_ja *specs = ((grn_db *)(ctx->impl->db))->specs;
  grn_io_win iw;
  uint32_t encoded_spec_size;
  void *encoded_spec = grn_ja_ref(ctx, specs, id, &iw, &encoded_spec_size);
  if (encoded_spec_size == 0) {
    return GRN_DB_VOID;
  }

  uint8_t type = GRN_DB_VOID;
  grn_obj_spec *spec;
  grn_obj decoded_spec;
  GRN_TEXT_INIT(&decoded_spec, GRN_OBJ_VECTOR);
  if (grn_obj_spec_unpack(ctx,
                          id,
                          encoded_spec,
                          encoded_spec_size,
                          &spec,
                          &decoded_spec,
                          "[ctx][is-table]")) {
    type = spec->header.type;
  }
  GRN_OBJ_FIN(ctx, &decoded_spec);
  grn_ja_unref(ctx, &iw);

  return type;
}

static grn_rc
grn_ctx_remove_internal(
  grn_ctx *ctx, grn_id id, const char *name, uint32_t name_size, uint32_t flags)
{
  grn_obj *db = ctx->impl->db;
  uint8_t type = grn_ctx_get_type(ctx, id);
  if (grn_obj_type_is_table(type)) {
    if (name_size > 0) {
      if (flags & GRN_OBJ_REMOVE_DEPENDENT) {
        grn_rc rc =
          remove_reference_tables_raw(ctx, id, name, name_size, db, flags);
        if (rc != GRN_SUCCESS) {
          return rc;
        }
      } else {
        if (!is_removable_table_raw(ctx, id, name, name_size, db)) {
          return ctx->rc;
        }
      }
    }

    grn_rc rc = remove_index_full_scan(ctx, id, flags);
    if (rc != GRN_SUCCESS) {
      return rc;
    }

    if (name_size > 0) {
      rc = remove_columns_raw(ctx, id, name, name_size, flags);
      if (rc != GRN_SUCCESS) {
        return rc;
      }
    }
  } else if (grn_obj_type_is_column(type)) {
    switch (type) {
    case GRN_COLUMN_VAR_SIZE:
    case GRN_COLUMN_INDEX:
      delete_source_hook_full_scan(ctx, id, flags);
      if (ctx->rc != GRN_SUCCESS) {
        return ctx->rc;
      }
      break;
    default:
      break;
    }
    grn_rc rc = remove_index_full_scan(ctx, id, flags);
    if (rc != GRN_SUCCESS) {
      return rc;
    }
  }

  grn_obj_delete_by_id(ctx, db, id, true);
  {
    char path[PATH_MAX];
    grn_obj_path_by_id(ctx, db, id, path);
    grn_io_remove_if_exist(ctx, path);
    grn_strcat(path, PATH_MAX, ".c");
    grn_io_remove_if_exist(ctx, path);
  }
  grn_ctx_done_removing(ctx, id);

  return ctx->rc;
}

grn_rc
grn_ctx_remove(grn_ctx *ctx, const char *name, int name_size, uint32_t flags)
{
  const char *tag = "[ctx][remove]";

  GRN_API_ENTER;

  if (name_size < 0) {
    name_size = strlen(name);
  }

  if (!(ctx->impl && ctx->impl->db)) {
    ERR(GRN_INVALID_ARGUMENT,
        "%s[%.*s] database isn't initialized",
        tag,
        name_size,
        name);
    GRN_API_RETURN(ctx->rc);
  }

  grn_obj *obj = grn_ctx_get(ctx, name, name_size);
  if (obj) {
    grn_rc rc = grn_obj_remove_flags(ctx, obj, flags);
    if (rc == GRN_SUCCESS) {
      GRN_API_RETURN(rc);
    }
    if (!(flags & GRN_OBJ_REMOVE_ENSURE)) {
      GRN_API_RETURN(rc);
    }
  } else {
    if (!(flags & GRN_OBJ_REMOVE_ENSURE)) {
      ERR(GRN_INVALID_ARGUMENT,
          "%s[%.*s] object doesn't exist",
          tag,
          name_size,
          name);
      GRN_API_RETURN(ctx->rc);
    }
  }
  ERRCLR(ctx);

  grn_obj *db = ctx->impl->db;
  grn_id id = grn_table_get(ctx, db, name, name_size);
  if (id == GRN_ID_NIL) {
    if (!(flags & GRN_OBJ_REMOVE_ENSURE)) {
      ERR(GRN_INVALID_ARGUMENT,
          "[ctx][remove] nonexistent object: <%.*s>",
          name_size,
          name);
    }
    GRN_API_RETURN(ctx->rc);
  }
  grn_rc rc = grn_ctx_remove_internal(ctx, id, name, name_size, flags);
  GRN_API_RETURN(rc);
}

static grn_rc
grn_ctx_remove_by_id_internal(grn_ctx *ctx,
                              grn_id id,
                              uint32_t flags,
                              bool is_top_level)
{
  const char *tag = "[ctx][remove][id]";

  if (id == GRN_ID_NIL) {
    return GRN_SUCCESS;
  }

  grn_obj *obj = grn_ctx_at(ctx, id);
  if (obj) {
    grn_rc rc;
    if (is_top_level) {
      rc = grn_obj_remove_flags(ctx, obj, flags);
    } else {
      rc = grn_obj_remove_internal(ctx, obj, flags);
    }
    if (rc == GRN_SUCCESS) {
      return rc;
    }
    if (!(flags & GRN_OBJ_REMOVE_ENSURE)) {
      return rc;
    }
  } else {
    if (!(flags & GRN_OBJ_REMOVE_ENSURE)) {
      ERR(GRN_INVALID_ARGUMENT, "%s[%u] object doesn't exist", tag, id);
      return ctx->rc;
    }
  }
  ERRCLR(ctx);

  grn_obj *db = ctx->impl->db;
  int name_size;
  const char *name = _grn_table_key(ctx, db, id, &name_size);
  return grn_ctx_remove_internal(ctx, id, name, name_size, flags);
}

grn_rc
grn_ctx_remove_by_id(grn_ctx *ctx, grn_id id, uint32_t flags)
{
  const char *tag = "[ctx][remove][id]";

  GRN_API_ENTER;

  if (!(ctx->impl && ctx->impl->db)) {
    ERR(GRN_INVALID_ARGUMENT, "%s[%u] database isn't initialized", tag, id);
    GRN_API_RETURN(ctx->rc);
  }

  grn_rc rc = grn_ctx_remove_by_id_internal(ctx, id, flags, true);
  GRN_API_RETURN(rc);
}

grn_rc
grn_table_update_by_id(grn_ctx *ctx,
                       grn_obj *table,
                       grn_id id,
                       const void *dest_key,
                       unsigned int dest_key_size)
{
  grn_rc rc = GRN_OPERATION_NOT_SUPPORTED;
  GRN_API_ENTER;
  if (table->header.type == GRN_TABLE_DAT_KEY) {
    grn_dat *dat = (grn_dat *)table;
    GRN_TABLE_LOCK_BEGIN(ctx, table)
    {
      rc = grn_dat_update_by_id(ctx, dat, id, dest_key, dest_key_size);
    }
    GRN_TABLE_LOCK_END(ctx);
  }
  GRN_API_RETURN(rc);
}

grn_rc
grn_table_update(grn_ctx *ctx,
                 grn_obj *table,
                 const void *src_key,
                 unsigned int src_key_size,
                 const void *dest_key,
                 unsigned int dest_key_size)
{
  grn_rc rc = GRN_OPERATION_NOT_SUPPORTED;
  GRN_API_ENTER;
  if (table->header.type == GRN_TABLE_DAT_KEY) {
    rc = grn_dat_update(ctx,
                        (grn_dat *)table,
                        src_key,
                        src_key_size,
                        dest_key,
                        dest_key_size);
  }
  GRN_API_RETURN(rc);
}

grn_rc
grn_obj_rename(grn_ctx *ctx,
               grn_obj *obj,
               const char *name,
               unsigned int name_size)
{
  grn_rc rc = GRN_INVALID_ARGUMENT;
  GRN_API_ENTER;
  if (ctx && ctx->impl && GRN_DB_P(ctx->impl->db) && GRN_DB_OBJP(obj) &&
      !IS_TEMP(obj)) {
    grn_db *s = (grn_db *)ctx->impl->db;
    grn_obj *keys = (grn_obj *)s->keys;
    rc = grn_table_update_by_id(ctx, keys, DB_OBJ(obj)->id, name, name_size);
  }
  GRN_API_RETURN(rc);
}

grn_rc
grn_table_rename(grn_ctx *ctx,
                 grn_obj *table,
                 const char *name,
                 unsigned int name_size)
{
  grn_rc rc = GRN_INVALID_ARGUMENT;
  grn_hash *cols;

  GRN_API_ENTER;

  if (!GRN_OBJ_TABLEP(table)) {
    char table_name[GRN_TABLE_MAX_KEY_SIZE];
    int table_name_size;
    table_name_size =
      grn_obj_name(ctx, table, table_name, GRN_TABLE_MAX_KEY_SIZE);
    rc = GRN_INVALID_ARGUMENT;
    ERR(rc,
        "[table][rename] isn't table: <%.*s> -> <%.*s>",
        table_name_size,
        table_name,
        name_size,
        name);
    goto exit;
  }
  if (IS_TEMP(table)) {
    rc = GRN_INVALID_ARGUMENT;
    ERR(rc,
        "[table][rename] temporary table doesn't have name: "
        "(anonymous) -> <%.*s>",
        name_size,
        name);
    goto exit;
  }

  if ((cols = grn_hash_create(ctx,
                              NULL,
                              sizeof(grn_id),
                              0,
                              GRN_OBJ_TABLE_HASH_KEY | GRN_HASH_TINY))) {
    grn_table_columns(ctx, table, "", 0, (grn_obj *)cols);
    if (!(rc = grn_obj_rename(ctx, table, name, name_size))) {
      grn_id *key;
      char fullname[GRN_TABLE_MAX_KEY_SIZE];
      grn_memcpy(fullname, name, name_size);
      fullname[name_size] = GRN_DB_DELIMITER;
      GRN_HASH_EACH(ctx, cols, id, &key, NULL, NULL, {
        grn_obj *col = grn_ctx_at(ctx, *key);
        if (col) {
          int colname_len =
            grn_column_name(ctx,
                            col,
                            fullname + name_size + 1,
                            GRN_TABLE_MAX_KEY_SIZE - name_size - 1);
          if (colname_len) {
            if ((rc = grn_obj_rename(ctx,
                                     col,
                                     fullname,
                                     name_size + 1 + colname_len))) {
              break;
            }
          }
        }
      });
    }
    grn_hash_close(ctx, cols);
  }
exit:
  GRN_API_RETURN(rc);
}

grn_rc
grn_column_rename(grn_ctx *ctx,
                  grn_obj *column,
                  const char *name,
                  unsigned int name_size)
{
  grn_rc rc = GRN_INVALID_ARGUMENT;
  GRN_API_ENTER;
  if (GRN_DB_OBJP(column)) {
    char fullname[GRN_TABLE_MAX_KEY_SIZE];
    grn_db *s = (grn_db *)DB_OBJ(column)->db;
    int len = grn_table_get_key(ctx,
                                s->keys,
                                DB_OBJ(column)->header.domain,
                                fullname,
                                GRN_TABLE_MAX_KEY_SIZE);
    if (name_size + 1 + len > GRN_TABLE_MAX_KEY_SIZE) {
      ERR(GRN_INVALID_ARGUMENT,
          "[column][rename] too long column name: required name_size(%d) < %d"
          ": <%.*s>.<%.*s>",
          name_size,
          GRN_TABLE_MAX_KEY_SIZE - 1 - len,
          len,
          fullname,
          name_size,
          name);
      goto exit;
    }
    fullname[len] = GRN_DB_DELIMITER;
    grn_memcpy(fullname + len + 1, name, name_size);
    name_size += len + 1;
    rc = grn_obj_rename(ctx, column, fullname, name_size);
    if (rc == GRN_SUCCESS) {
      grn_obj_touch(ctx, column, NULL);
    }
  }
exit:
  GRN_API_RETURN(rc);
}

grn_rc
grn_obj_path_rename(grn_ctx *ctx, const char *old_path, const char *new_path)
{
  GRN_API_ENTER;
  GRN_API_RETURN(GRN_SUCCESS);
}

/* db must be validated by caller */
grn_id
grn_obj_register(grn_ctx *ctx,
                 grn_obj *db,
                 const char *name,
                 unsigned int name_size)
{
  grn_id id = GRN_ID_NIL;
  if (name && name_size) {
    grn_db *s = (grn_db *)db;
    int added;
    if (!(id = grn_table_add(ctx, s->keys, name, name_size, &added))) {
      grn_rc rc;
      char errbuf[GRN_CTX_MSGSIZE];
      rc = ctx->rc;
      if (rc == GRN_SUCCESS) {
        rc = GRN_NO_MEMORY_AVAILABLE;
      }
      grn_strcpy(errbuf, GRN_CTX_MSGSIZE, ctx->errbuf);
      ERR(rc,
          "[object][register] failed to register a name: <%.*s>%s%s%s",
          name_size,
          name,
          ctx->rc == GRN_SUCCESS ? "" : ": <",
          ctx->rc == GRN_SUCCESS ? "" : errbuf,
          ctx->rc == GRN_SUCCESS ? "" : ">");
    } else if (!added) {
      ERR(GRN_INVALID_ARGUMENT,
          "[object][register] already used name was assigned: <%.*s>",
          name_size,
          name);
      id = GRN_ID_NIL;
    }
  } else {
    grn_ctx *target_ctx = ctx;
    while (target_ctx->impl->parent) {
      target_ctx = target_ctx->impl->parent;
    }
    if (target_ctx->impl && target_ctx->impl->values) {
      if (target_ctx != ctx) {
        CRITICAL_SECTION_ENTER(target_ctx->impl->temporary_objects_lock);
      }
      id = grn_array_add(target_ctx, target_ctx->impl->values, NULL);
      if (id == GRN_ID_NIL) {
        grn_rc rc = ctx->rc;
        if (rc == GRN_SUCCESS) {
          rc = GRN_NO_MEMORY_AVAILABLE;
        }
        ERR(rc,
            "[object][register] failed to register a temporary object: %p(%p)",
            target_ctx,
            ctx);
      } else {
        id |= GRN_OBJ_TMP_OBJECT;
      }
      if (target_ctx != ctx) {
        CRITICAL_SECTION_LEAVE(target_ctx->impl->temporary_objects_lock);
      }
    }
  }
  return id;
}

grn_rc
grn_obj_delete_by_id(grn_ctx *ctx, grn_obj *db, grn_id id, bool remove_p)
{
  grn_rc rc = GRN_INVALID_ARGUMENT;
  GRN_API_ENTER;
  if (id) {
    if (id & GRN_OBJ_TMP_OBJECT) {
      grn_ctx *target_ctx = ctx;
      while (target_ctx->impl->parent) {
        target_ctx = target_ctx->impl->parent;
      }
      if (target_ctx->impl) {
        if (id & GRN_OBJ_TMP_COLUMN) {
          if (target_ctx->impl->temporary_columns) {
            if (target_ctx != ctx) {
              CRITICAL_SECTION_ENTER(target_ctx->impl->temporary_objects_lock);
            }
            grn_log_reference_count("%p: delete: %u\n", target_ctx, id);
            rc = grn_pat_delete_by_id(
              target_ctx,
              target_ctx->impl->temporary_columns,
              id & ~(GRN_OBJ_TMP_COLUMN | GRN_OBJ_TMP_OBJECT),
              NULL);
            if (target_ctx != ctx) {
              CRITICAL_SECTION_LEAVE(target_ctx->impl->temporary_objects_lock);
            }
          }
        } else {
          if (target_ctx->impl->values) {
            if (target_ctx != ctx) {
              CRITICAL_SECTION_ENTER(target_ctx->impl->temporary_objects_lock);
            }
            grn_log_reference_count("%p: delete: %u\n", ctx, id);
            rc = grn_array_delete_by_id(target_ctx,
                                        target_ctx->impl->values,
                                        id & ~GRN_OBJ_TMP_OBJECT,
                                        NULL);
            if (target_ctx != ctx) {
              CRITICAL_SECTION_LEAVE(target_ctx->impl->temporary_objects_lock);
            }
          }
        }
      }
    } else {
      db_value *vp;
      grn_db *s = (grn_db *)db;
      if ((vp = grn_tiny_array_at(&s->values, id))) {
        grn_log_reference_count("%p: delete: %u: %u\n", ctx, id, vp->lock);
        GRN_ASSERT(!vp->lock);
        vp->lock = 0;
        vp->ptr = NULL;
        vp->done = 0;
      }
      if (remove_p) {
        rc = grn_ja_put(ctx, s->specs, id, NULL, 0, GRN_OBJ_SET, NULL);
        grn_rc delete_rc = GRN_SUCCESS;
        switch (s->keys->header.type) {
        case GRN_TABLE_PAT_KEY:
          delete_rc = grn_pat_delete_by_id(ctx, (grn_pat *)s->keys, id, NULL);
          break;
        case GRN_TABLE_DAT_KEY:
          delete_rc = grn_dat_delete_by_id(ctx, (grn_dat *)s->keys, id, NULL);
          break;
        }
        if (rc == GRN_SUCCESS) {
          rc = delete_rc;
        }
      } else {
        rc = GRN_SUCCESS;
      }
    }
  }
  GRN_API_RETURN(rc);
}

grn_rc
grn_obj_path_by_id(grn_ctx *ctx, grn_obj *db, grn_id id, char *buffer)
{
  grn_rc rc = GRN_SUCCESS;
  GRN_API_ENTER;
  if (!GRN_DB_P(db) || !buffer) {
    rc = GRN_INVALID_ARGUMENT;
  } else {
    grn_db_generate_pathname(ctx, db, id, buffer);
  }
  GRN_API_RETURN(rc);
}

/* db must be validated by caller */
grn_rc
grn_db_obj_init(grn_ctx *ctx, grn_obj *db, grn_id id, grn_db_obj *obj)
{
  grn_rc rc = GRN_SUCCESS;
  if (id) {
    if (id & GRN_OBJ_TMP_OBJECT) {
      grn_ctx *target_ctx = ctx;
      while (target_ctx->impl->parent) {
        target_ctx = target_ctx->impl->parent;
      }
      if (id & GRN_OBJ_TMP_COLUMN) {
        if (target_ctx->impl && target_ctx->impl->temporary_columns) {
          grn_id real_id = id & ~(GRN_OBJ_TMP_COLUMN | GRN_OBJ_TMP_OBJECT);
          if (target_ctx != ctx) {
            CRITICAL_SECTION_ENTER(target_ctx->impl->temporary_objects_lock);
          }
          rc = grn_pat_set_value(target_ctx,
                                 target_ctx->impl->temporary_columns,
                                 real_id,
                                 &obj,
                                 GRN_OBJ_SET);
          if (target_ctx != ctx) {
            CRITICAL_SECTION_LEAVE(target_ctx->impl->temporary_objects_lock);
          }
        }
      } else {
        if (target_ctx->impl && target_ctx->impl->values) {
          if (target_ctx != ctx) {
            CRITICAL_SECTION_ENTER(target_ctx->impl->temporary_objects_lock);
          }
          rc = grn_array_set_value(target_ctx,
                                   target_ctx->impl->values,
                                   id & ~GRN_OBJ_TMP_OBJECT,
                                   &obj,
                                   GRN_OBJ_SET);
          if (target_ctx != ctx) {
            CRITICAL_SECTION_LEAVE(target_ctx->impl->temporary_objects_lock);
          }
        }
      }
    } else {
      db_value *vp;
      vp = grn_tiny_array_at(&((grn_db *)db)->values, id);
      if (!vp) {
        rc = GRN_NO_MEMORY_AVAILABLE;
        ERR(rc, "grn_tiny_array_at failed (%d)", id);
        return rc;
      }
      vp->lock = 1;
      vp->ptr = (grn_obj *)obj;
      grn_log_reference_count("%p: init: %u: %u\n", ctx, id, vp->lock);
    }
  }
  obj->id = id;
  obj->db = db;
  obj->source = NULL;
  obj->source_size = 0;
  {
    grn_hook_entry entry;
    for (entry = 0; entry < GRN_N_HOOK_ENTRIES; entry++) {
      obj->hooks[entry] = NULL;
    }
  }
  grn_obj_spec_save(ctx, obj);
  return rc;
}

/* The size of buffer's must be PATH_MAX */
void
grn_obj_spec_get_path(grn_ctx *ctx,
                      grn_obj_spec *spec,
                      grn_id id,
                      char *buffer,
                      grn_db *db,
                      grn_obj *decoded_spec)
{
  if (spec->header.flags & GRN_OBJ_CUSTOM_NAME) {
    const char *path;
    unsigned int size = grn_vector_get_element(ctx,
                                               decoded_spec,
                                               GRN_SERIALIZED_SPEC_INDEX_PATH,
                                               &path,
                                               NULL,
                                               NULL);
    if (size >= PATH_MAX) {
      ERR(GRN_FILENAME_TOO_LONG,
          "[spec][path] too long path: %u >= %u: <%.*s>",
          size,
          PATH_MAX,
          (int)size,
          path);
    }
    grn_memcpy(buffer, path, size);
    buffer[size] = '\0';
  } else if (spec->header.flags & GRN_OBJ_PERSISTENT) {
    grn_db_generate_pathname(ctx, (grn_obj *)db, id, buffer);
  } else {
    buffer[0] = '\0';
  }
}

#define UNPACK_INFO(spec, decoded_spec)                                        \
  do {                                                                         \
    if (vp->ptr) {                                                             \
      const char *p;                                                           \
      uint32_t size;                                                           \
      grn_db_obj *r = DB_OBJ(vp->ptr);                                         \
      r->header = spec->header;                                                \
      r->id = id;                                                              \
      r->range = spec->range;                                                  \
      r->db = (grn_obj *)s;                                                    \
      size = grn_vector_get_element(ctx,                                       \
                                    decoded_spec,                              \
                                    GRN_SERIALIZED_SPEC_INDEX_SOURCE,          \
                                    &p,                                        \
                                    NULL,                                      \
                                    NULL);                                     \
      if (size) {                                                              \
        if ((r->source = GRN_MALLOC(size))) {                                  \
          grn_memcpy(r->source, p, size);                                      \
          r->source_size = size;                                               \
        }                                                                      \
      }                                                                        \
      size = grn_vector_get_element(ctx,                                       \
                                    decoded_spec,                              \
                                    GRN_SERIALIZED_SPEC_INDEX_HOOK,            \
                                    &p,                                        \
                                    NULL,                                      \
                                    NULL);                                     \
      grn_hook_unpack(ctx, r, p, size);                                        \
    }                                                                          \
  } while (0)

static void
grn_table_modules_unpack(grn_ctx *ctx,
                         grn_obj *spec_vector,
                         uint32_t index,
                         grn_obj *table_modules,
                         grn_obj *table_module_procs,
                         const char *tag)
{
  if (grn_vector_size(ctx, spec_vector) <= index) {
    return;
  }

  grn_table_modules_rewind(ctx, table_modules);

  grn_id *ids;
  unsigned int element_size = grn_vector_get_element(ctx,
                                                     spec_vector,
                                                     index,
                                                     (const char **)(&ids),
                                                     NULL,
                                                     NULL);
  size_t n_ids = element_size / sizeof(grn_id);
  size_t i;
  for (i = 0; i < n_ids; i++) {
    grn_id id = ids[i];
    grn_obj *proc = grn_ctx_at(ctx, id);
    if (!proc) {
      ERR(GRN_INVALID_ARGUMENT,
          "%s nonexistent table module proc ID: %d",
          tag,
          id);
      return;
    }
    grn_table_modules_add(ctx, table_modules, proc);
    if (table_module_procs) {
      GRN_PTR_PUT(ctx, table_module_procs, proc);
    }
  }
}

bool
grn_obj_spec_unpack(grn_ctx *ctx,
                    grn_id id,
                    void *encoded_spec,
                    uint32_t encoded_spec_size,
                    grn_obj_spec **spec,
                    grn_obj *decoded_spec,
                    const char *error_message_tag)
{
  grn_obj *db;
  grn_db *db_raw;
  grn_rc rc;
  uint32_t spec_size;

  db = ctx->impl->db;
  db_raw = (grn_db *)db;

  rc = grn_vector_unpack(ctx,
                         decoded_spec,
                         encoded_spec,
                         encoded_spec_size,
                         0,
                         NULL);
  if (rc != GRN_SUCCESS) {
    const char *name;
    uint32_t name_size;
    name = _grn_table_key(ctx, db, id, &name_size);
    GRN_LOG((ctx),
            GRN_LOG_ERROR,
            "%s: failed to decode spec: <%u>(<%.*s>):<%u>: %s",
            error_message_tag,
            id,
            name_size,
            name,
            encoded_spec_size,
            grn_rc_to_string(rc));
    return false;
  }

  spec_size = grn_vector_get_element(ctx,
                                     decoded_spec,
                                     GRN_SERIALIZED_SPEC_INDEX_SPEC,
                                     (const char **)spec,
                                     NULL,
                                     NULL);
  if (spec_size == 0) {
    const char *name;
    uint32_t name_size;
    name = _grn_table_key(ctx, db, id, &name_size);
    GRN_LOG(ctx,
            GRN_LOG_ERROR,
            "%s: spec value is empty: <%u>(<%.*s>)",
            error_message_tag,
            id,
            name_size,
            name);
    return false;
  }

  return true;
}

static inline bool
grn_db_value_lock(grn_ctx *ctx,
                  grn_id id,
                  db_value *vp,
                  uint32_t *current_lock_output)
{
  bool is_locked = true;
  uint32_t current_lock = 0;
  uint32_t *lock_pointer = &(vp->lock);
  uint32_t n_trials = 0;
  for (;; n_trials++) {
    GRN_ATOMIC_ADD_EX(lock_pointer, 1, current_lock);
    if (current_lock < GRN_IO_MAX_REF) {
      break;
    }
    GRN_ATOMIC_ADD_EX(lock_pointer, -1, current_lock);
    if (n_trials >= 1000) {
      GRN_LOG(ctx,
              GRN_LOG_NOTICE,
              "[db][value][lock] failed to lock: "
              "n_trials:<%u> "
              "id:<%u> "
              "lock:<%u> "
              "address:<%p>",
              n_trials,
              id,
              vp->lock,
              vp->ptr);
      is_locked = false;
      break;
    }
    GRN_FUTEX_WAIT(lock_pointer);
  }
  grn_log_reference_count("%p: lock: %u: %u\n", ctx, id, current_lock);
  *current_lock_output = current_lock;
  return is_locked;
}

static inline uint32_t
grn_db_value_unlock(grn_ctx *ctx, grn_id id, db_value *vp)
{
  uint32_t current_lock = 0;
  uint32_t *lock_pointer = &(vp->lock);
  GRN_ATOMIC_ADD_EX(lock_pointer, -1, current_lock);
  grn_log_reference_count("%p: unlock: %u: %u\n", ctx, id, current_lock);
  return current_lock;
}

static inline bool
grn_db_value_wait(grn_ctx *ctx, grn_id id, db_value *vp)
{
  bool succeeded = true;
  uint32_t n_trials;
  grn_log_reference_count("%p: wait: start: %u: %u\n", ctx, id, vp->lock);
  for (n_trials = 0; !vp->ptr; n_trials++) {
    if (n_trials >= 3000) {
      GRN_LOG(ctx,
              GRN_LOG_NOTICE,
              "[db][value][wait] failed to wait: "
              "n_trials:<%u> "
              "id:<%u> "
              "lock:<%u> "
              "address:<%p>",
              n_trials,
              id,
              vp->lock,
              vp->ptr);
      succeeded = false;
      break;
    }
    GRN_FUTEX_WAIT(&vp->ptr);
  }
  grn_log_reference_count("%p: wait: done: %u: %u\n", ctx, id, vp->lock);
  return succeeded;
}

static inline bool
grn_obj_type_is_open_close_log_target(grn_ctx *ctx, uint8_t type)
{
  switch (type) {
  case GRN_TYPE:
  case GRN_PROC:
    return false;
  default:
    return true;
  }
}

#define GRN_LOG_REFERENCE_COUNT GRN_LOG_DUMP

static inline bool
grn_reference_count_should_log(grn_ctx *ctx, uint8_t type)
{
  if (!grn_enable_reference_count) {
    return false;
  }
  if (!grn_obj_type_is_open_close_log_target(ctx, type)) {
    return false;
  }
  return grn_logger_pass(ctx, GRN_LOG_REFERENCE_COUNT);
}

grn_obj *
grn_ctx_at(grn_ctx *ctx, grn_id id)
{
  grn_obj *res = NULL;
  if (!ctx || !ctx->impl || !id) {
    return res;
  }
  GRN_API_ENTER;
  if (id & GRN_OBJ_TMP_OBJECT) {
    grn_ctx *target_ctx = ctx;
    while (target_ctx->impl->parent) {
      target_ctx = target_ctx->impl->parent;
    }
    if (id & GRN_OBJ_TMP_COLUMN) {
      if (target_ctx->impl->temporary_columns) {
        grn_id real_id = id & ~(GRN_OBJ_TMP_COLUMN | GRN_OBJ_TMP_OBJECT);
        grn_log_reference_count("%p: at: start: %u\n", target_ctx, real_id);
        grn_obj **tmp_obj;
        uint32_t size;
        tmp_obj =
          (grn_obj **)grn_pat_get_value_(target_ctx,
                                         target_ctx->impl->temporary_columns,
                                         real_id,
                                         &size);
        if (tmp_obj) {
          res = *tmp_obj;
        }
      }
    } else {
      if (target_ctx->impl->values) {
        grn_id real_id = id & ~GRN_OBJ_TMP_OBJECT;
        grn_log_reference_count("%p: at: start: %u\n", target_ctx, real_id);
        grn_obj **tmp_obj;
        tmp_obj =
          _grn_array_get_value(target_ctx, target_ctx->impl->values, real_id);
        if (tmp_obj) {
          res = *tmp_obj;
        }
      }
    }
    if (res) {
      DB_OBJ(res)->reference_count++;
      grn_log_reference_count("%p: at: done: %u: %u\n",
                              target_ctx,
                              DB_OBJ(res)->id,
                              DB_OBJ(res)->reference_count);
    }
  } else {
    grn_db *s = (grn_db *)ctx->impl->db;
    if (s) {
      db_value *vp;
      uint32_t lock = 0;
      if (!(vp = grn_tiny_array_at(&s->values, id))) {
        goto exit;
      }
      /* We can skip opened check with lock for built-in objects
       * because built-in objects are opened on DB open and never
       * closed until DB is closed at least with the current
       * design. So the object is opened (vp->ptr != NULL, vp->ptr is
       * NULL only when no associated object), we can safely return
       * the opened object directly without lock. */
      if (id < GRN_N_RESERVED_TYPES && vp->ptr) {
        res = vp->ptr;
        goto exit;
      }
      grn_log_reference_count("%p: at: start: %u\n", ctx, id);
      if (grn_enable_reference_count) {
        if (!grn_db_value_lock(ctx, id, vp, &lock)) {
          const char *name;
          uint32_t name_size = 0;
          name = _grn_table_key(ctx, (grn_obj *)s, id, &name_size);
          ERR(GRN_NO_LOCKS_AVAILABLE,
              "[at] failed to lock: <%u>(<%.*s>)",
              id,
              name_size,
              name);
          goto exit;
        }
      }
      if (s->specs && !vp->ptr /* && !vp->done */) {
        if (!grn_enable_reference_count) {
          if (!grn_db_value_lock(ctx, id, vp, &lock)) {
            const char *name;
            uint32_t name_size = 0;
            name = _grn_table_key(ctx, (grn_obj *)s, id, &name_size);
            ERR(GRN_NO_LOCKS_AVAILABLE,
                "[at] failed to lock: "
                "<%u>(<%.*s>)",
                id,
                name_size,
                name);
            goto exit;
          }
        }
        if (lock == 0) {
          grn_io_win iw;
          uint32_t encoded_spec_size;
          void *encoded_spec;

          encoded_spec = grn_ja_ref(ctx, s->specs, id, &iw, &encoded_spec_size);
          if (encoded_spec) {
            bool success;
            grn_obj_spec *spec;
            grn_obj decoded_spec;

            GRN_OBJ_INIT(&decoded_spec, GRN_VECTOR, 0, GRN_DB_TEXT);
            success = grn_obj_spec_unpack(ctx,
                                          id,
                                          encoded_spec,
                                          encoded_spec_size,
                                          &spec,
                                          &decoded_spec,
                                          "grn_ctx_at");
            if (success) {
              char buffer[PATH_MAX];
              switch (spec->header.type) {
              case GRN_TYPE:
                vp->ptr = (grn_obj *)grn_type_open(ctx, spec);
                UNPACK_INFO(spec, &decoded_spec);
                break;
              case GRN_TABLE_HASH_KEY:
                grn_obj_spec_get_path(ctx, spec, id, buffer, s, &decoded_spec);
                vp->ptr = (grn_obj *)grn_hash_open(ctx, buffer);
                if (vp->ptr) {
                  grn_hash *hash = (grn_hash *)(vp->ptr);
                  grn_obj_flags flags = vp->ptr->header.flags;
                  UNPACK_INFO(spec, &decoded_spec);
                  vp->ptr->header.flags = flags;
                  grn_table_modules_unpack(
                    ctx,
                    &decoded_spec,
                    GRN_SERIALIZED_SPEC_INDEX_TOKEN_FILTERS,
                    &(hash->token_filters),
                    &(hash->token_filter_procs),
                    "[at][token-filters]");
                  grn_table_modules_unpack(
                    ctx,
                    &decoded_spec,
                    GRN_SERIALIZED_SPEC_INDEX_NORMALIZERS,
                    &(hash->normalizers),
                    NULL,
                    "[at][normalizers]");
                }
                break;
              case GRN_TABLE_PAT_KEY:
                grn_obj_spec_get_path(ctx, spec, id, buffer, s, &decoded_spec);
                vp->ptr = (grn_obj *)grn_pat_open(ctx, buffer);
                if (vp->ptr) {
                  grn_pat *pat = (grn_pat *)(vp->ptr);
                  grn_obj_flags flags = vp->ptr->header.flags;
                  UNPACK_INFO(spec, &decoded_spec);
                  vp->ptr->header.flags = flags;
                  grn_table_modules_unpack(
                    ctx,
                    &decoded_spec,
                    GRN_SERIALIZED_SPEC_INDEX_TOKEN_FILTERS,
                    &(pat->token_filters),
                    &(pat->token_filter_procs),
                    "[at][token-filters]");
                  grn_table_modules_unpack(
                    ctx,
                    &decoded_spec,
                    GRN_SERIALIZED_SPEC_INDEX_NORMALIZERS,
                    &(pat->normalizers),
                    NULL,
                    "[at][normalizers]");
                  if (pat->tokenizer.proc) {
                    grn_pat_cache_enable(ctx,
                                         pat,
                                         GRN_TABLE_PAT_KEY_CACHE_SIZE);
                  }
                }
                break;
              case GRN_TABLE_DAT_KEY:
                grn_obj_spec_get_path(ctx, spec, id, buffer, s, &decoded_spec);
                vp->ptr = (grn_obj *)grn_dat_open(ctx, buffer);
                if (vp->ptr) {
                  grn_dat *dat = (grn_dat *)(vp->ptr);
                  grn_obj_flags flags = vp->ptr->header.flags;
                  UNPACK_INFO(spec, &decoded_spec);
                  vp->ptr->header.flags = flags;
                  grn_table_modules_unpack(
                    ctx,
                    &decoded_spec,
                    GRN_SERIALIZED_SPEC_INDEX_TOKEN_FILTERS,
                    &(dat->token_filters),
                    &(dat->token_filter_procs),
                    "[at][token-filters]");
                  grn_table_modules_unpack(
                    ctx,
                    &decoded_spec,
                    GRN_SERIALIZED_SPEC_INDEX_NORMALIZERS,
                    &(dat->normalizers),
                    NULL,
                    "[at][normalizers]");
                }
                break;
              case GRN_TABLE_NO_KEY:
                grn_obj_spec_get_path(ctx, spec, id, buffer, s, &decoded_spec);
                vp->ptr = (grn_obj *)grn_array_open(ctx, buffer);
                UNPACK_INFO(spec, &decoded_spec);
                break;
              case GRN_COLUMN_VAR_SIZE:
                grn_obj_spec_get_path(ctx, spec, id, buffer, s, &decoded_spec);
                vp->ptr = (grn_obj *)grn_ja_open(ctx, buffer);
                UNPACK_INFO(spec, &decoded_spec);
                {
                  grn_raw_string generator = grn_generator_unpack(
                    ctx,
                    &decoded_spec,
                    GRN_SERIALIZED_SPEC_INDEX_JA_GENERATOR);
                  if (generator.length > 0) {
                    grn_obj_set_generator(ctx,
                                          vp->ptr,
                                          generator,
                                          "[at][var-size][generator]");
                  }
                }
                break;
              case GRN_COLUMN_FIX_SIZE:
                grn_obj_spec_get_path(ctx, spec, id, buffer, s, &decoded_spec);
                vp->ptr = (grn_obj *)grn_ra_open(ctx, buffer);
                UNPACK_INFO(spec, &decoded_spec);
                {
                  grn_raw_string generator = grn_generator_unpack(
                    ctx,
                    &decoded_spec,
                    GRN_SERIALIZED_SPEC_INDEX_RA_GENERATOR);
                  if (generator.length > 0) {
                    grn_obj_set_generator(ctx,
                                          vp->ptr,
                                          generator,
                                          "[at][fix-size][generator]");
                  }
                }
                break;
              case GRN_COLUMN_INDEX:
                grn_obj_spec_get_path(ctx, spec, id, buffer, s, &decoded_spec);
                {
                  grn_obj *table = grn_ctx_at(ctx, spec->header.domain);
                  vp->ptr = (grn_obj *)grn_ii_open(ctx, buffer, table);
                  grn_obj_unlink(ctx, table);
                }
                UNPACK_INFO(spec, &decoded_spec);
                break;
              case GRN_PROC:
                grn_obj_spec_get_path(ctx, spec, id, buffer, s, &decoded_spec);
                grn_plugin_register(ctx, buffer);
                if (grn_enable_reference_count && vp->ptr) {
                  /* Registered proc by plugin must not be freed by
                   * grn_obj_unlink() for now. In the future, we may
                   * support reference count for proc registered by
                   * plugin.
                   *
                   * Registered proc by plugin isn't freed by
                   * grn_obj_unlink() in the process that executes
                   * plugin_register. Because plugin doesn't call
                   * grn_obj_unlink() against the returned object by
                   * grn_proc_create().
                   *
                   * Registered proc by plugin is freed by
                   * grn_obj_unlink() without this increment in the
                   * process that does not execute
                   * plugin_register. Because the initial reference
                   * count ("vp->lock = 1") in grn_db_obj_init()
                   * (called from grn_proc_create()) is reused by this
                   * grn_ctx_at(). If we increment the reference count
                   * here, the registered proc by plugin here isn't
                   * freed by grn_obj_unlink() in the process that
                   * does not execute plugin_register. */
                  vp->lock++;
                  grn_log_reference_count("%p: at: proc: increment: %u: %u\n",
                                          ctx,
                                          id,
                                          vp->lock);
                }
                break;
              case GRN_EXPR:
                {
                  const char *p;
                  uint32_t size;
                  uint8_t *u;
                  size = grn_vector_get_element(ctx,
                                                &decoded_spec,
                                                GRN_SERIALIZED_SPEC_INDEX_EXPR,
                                                &p,
                                                NULL,
                                                NULL);
                  u = (uint8_t *)p;
                  vp->ptr = grn_expr_open(ctx, spec, u, u + size);
                }
                break;
              }
              if (vp->ptr) {
                if (grn_reference_count_should_log(ctx, spec->header.type)) {
                  const char *name;
                  uint32_t name_size = 0;
                  name = _grn_table_key(ctx, (grn_obj *)s, id, &name_size);
                  GRN_LOG(ctx,
                          GRN_LOG_REFERENCE_COUNT,
                          "[obj][open] <%u>(<%.*s>):<%u>(<%s>)",
                          id,
                          name_size,
                          name,
                          spec->header.type,
                          grn_obj_type_to_string(spec->header.type));
                }

                switch (vp->ptr->header.type) {
                case GRN_TABLE_HASH_KEY:
                case GRN_TABLE_PAT_KEY:
                case GRN_TABLE_DAT_KEY:
                case GRN_TABLE_NO_KEY:
                case GRN_COLUMN_FIX_SIZE:
                case GRN_COLUMN_VAR_SIZE:
                case GRN_COLUMN_INDEX:
                  {
                    grn_obj *space;
                    space = ctx->impl->temporary_open_spaces.current;
                    if (space) {
                      GRN_PTR_PUT(ctx, space, vp->ptr);
                    }
                  }
                  break;
                }
              } else {
                const char *name;
                uint32_t name_size = 0;
                name = _grn_table_key(ctx, (grn_obj *)s, id, &name_size);
                GRN_LOG(ctx,
                        GRN_LOG_ERROR,
                        "grn_ctx_at: failed to open object: "
                        "<%u>(<%.*s>):<%u>(<%s>)",
                        id,
                        name_size,
                        name,
                        spec->header.type,
                        grn_obj_type_to_string(spec->header.type));
              }
            }
            GRN_OBJ_FIN(ctx, &decoded_spec);
            grn_ja_unref(ctx, &iw);
          }
          if (grn_enable_reference_count) {
            if (!vp->ptr) {
              grn_db_value_unlock(ctx, id, vp);
            }
          } else {
            grn_db_value_unlock(ctx, id, vp);
          }
          vp->done = 1;
          GRN_FUTEX_WAKE(&vp->ptr);
        } else {
          if (!grn_db_value_wait(ctx, id, vp)) {
            const char *name;
            uint32_t name_size = 0;
            name = _grn_table_key(ctx, (grn_obj *)s, id, &name_size);
            grn_log_reference_count(
              "%p: at: done: failed to wait: %u: %u: %p\n",
              ctx,
              id,
              vp->lock,
              vp->ptr);
            ERR(GRN_NO_LOCKS_AVAILABLE,
                "[at] failed to wait: "
                "<%u>(<%.*s>)",
                id,
                name_size,
                name);
            grn_db_value_unlock(ctx, id, vp);
            goto exit;
          }
          if (!grn_enable_reference_count) {
            grn_db_value_unlock(ctx, id, vp);
          }
        }
      }
      res = vp->ptr;
      if (res && res->header.type == GRN_PROC) {
        grn_plugin_ensure_registered(ctx, res);
      }
      grn_log_reference_count("%p: at: done: %u: %u: %p\n",
                              ctx,
                              id,
                              vp->lock,
                              vp->ptr);
    }
  }
exit:
  GRN_API_RETURN(res);
}

bool
grn_ctx_is_opened(grn_ctx *ctx, grn_id id)
{
  bool is_opened = false;

  if (!ctx || !ctx->impl || !id) {
    return false;
  }

  GRN_API_ENTER;
  if (id & GRN_OBJ_TMP_OBJECT) {
    grn_ctx *target_ctx = ctx;
    while (target_ctx->impl->parent) {
      target_ctx = target_ctx->impl->parent;
    }
    if (target_ctx->impl->values) {
      grn_obj **tmp_obj;
      tmp_obj = _grn_array_get_value(target_ctx,
                                     target_ctx->impl->values,
                                     id & ~GRN_OBJ_TMP_OBJECT);
      if (tmp_obj) {
        is_opened = true;
      }
    }
  } else {
    grn_db *s = (grn_db *)ctx->impl->db;
    if (s) {
      db_value *vp;
      vp = grn_tiny_array_at(&s->values, id);
      if (vp && vp->ptr) {
        is_opened = true;
      }
    }
  }
  GRN_API_RETURN(is_opened);
}

grn_obj *
grn_obj_open(grn_ctx *ctx,
             unsigned char type,
             grn_obj_flags flags,
             grn_id domain)
{
  grn_obj *obj = GRN_CALLOC(sizeof(grn_obj));
  if (obj) {
    uint8_t init_flags =
      (uint8_t)(flags & (GRN_OBJ_VECTOR | GRN_OBJ_DO_SHALLOW_COPY));
    GRN_OBJ_INIT(obj, type, init_flags, domain);
    obj->header.impl_flags |= GRN_OBJ_ALLOCATED;
  }
  return obj;
}

grn_obj *
grn_obj_graft(grn_ctx *ctx, grn_obj *obj)
{
  grn_obj *new = grn_obj_open(ctx,
                              obj->header.type,
                              obj->header.impl_flags,
                              obj->header.domain);
  if (new) {
    /* todo : deep copy if (obj->header.impl_flags & GRN_OBJ_DO_SHALLOW_COPY) */
    new->u.b.head = obj->u.b.head;
    new->u.b.curr = obj->u.b.curr;
    new->u.b.tail = obj->u.b.tail;
    obj->u.b.head = NULL;
    obj->u.b.curr = NULL;
    obj->u.b.tail = NULL;
  }
  return new;
}

grn_rc
grn_pvector_fin(grn_ctx *ctx, grn_obj *obj)
{
  grn_rc rc;
  if (obj->header.impl_flags & GRN_OBJ_OWN) {
    /*
     * Note that GRN_OBJ_OWN should not be used outside the DB API function
     * because grn_obj_close is a DB API function.
     */
    unsigned int i, n_elements;
    n_elements = GRN_PTR_VECTOR_SIZE(obj);
    for (i = 0; i < n_elements; i++) {
      grn_obj *element = GRN_PTR_VALUE_AT(obj, n_elements - i - 1);
      if (element) {
        grn_obj_close(ctx, element);
      }
    }
  }
  obj->header.type = GRN_VOID;
  rc = grn_bulk_fin(ctx, obj);
  if (obj->header.impl_flags & GRN_OBJ_ALLOCATED) {
    GRN_FREE(obj);
  }
  return rc;
}

typedef void
grn_traverse_func(grn_ctx *ctx, grn_obj *obj, void *user_data);

typedef struct {
  bool is_close_opened_object_mode;
  grn_traverse_func *traverse;
  void *user_data;
  const char *tag;
} grn_obj_traverse_recursive_data;

static void
grn_obj_traverse_recursive_dispatch(grn_ctx *ctx,
                                    grn_obj_traverse_recursive_data *data,
                                    grn_obj *obj);

static void
grn_obj_traverse_recursive_db(grn_ctx *ctx,
                              grn_obj_traverse_recursive_data *data,
                              grn_obj *db)
{
  GRN_TABLE_EACH_BEGIN(ctx, db, cursor, id)
  {
    if (data->is_close_opened_object_mode) {
      grn_ctx_push_temporary_open_space(ctx);
    }

    grn_obj *object = grn_ctx_at(ctx, id);
    if (grn_obj_is_table(ctx, object)) {
      grn_obj_traverse_recursive_dispatch(ctx, data, object);
    } else {
      if (ctx->rc != GRN_SUCCESS) {
        ERRCLR(ctx);
      }
    }
    if (object) {
      grn_obj_unref(ctx, object);
    }

    if (data->is_close_opened_object_mode) {
      grn_ctx_pop_temporary_open_space(ctx);
    }

    if (ctx->rc != GRN_SUCCESS) {
      break;
    }
  }
  GRN_TABLE_EACH_END(ctx, cursor);
  if (ctx->rc != GRN_SUCCESS) {
    return;
  }

  data->traverse(ctx, db, data->user_data);
}

static void
grn_obj_traverse_recursive_table(grn_ctx *ctx,
                                 grn_obj_traverse_recursive_data *data,
                                 grn_obj *table)
{
  grn_hash *columns = grn_hash_create(ctx,
                                      NULL,
                                      sizeof(grn_id),
                                      0,
                                      GRN_OBJ_TABLE_HASH_KEY | GRN_HASH_TINY);
  if (!columns) {
    grn_rc rc = ctx->rc;
    if (rc == GRN_SUCCESS) {
      rc = GRN_NO_MEMORY_AVAILABLE;
    }
    char message[GRN_CTX_MSGSIZE];
    grn_strcpy(message, GRN_CTX_MSGSIZE, ctx->errbuf);
    char table_name[GRN_TABLE_MAX_KEY_SIZE];
    int table_name_size;
    table_name_size =
      grn_obj_name(ctx, table, table_name, GRN_TABLE_MAX_KEY_SIZE);
    ERR(rc,
        "%s[recursive] "
        "failed to create internal hash table "
        "to store columns: <%.*s>: %s",
        data->tag,
        table_name_size,
        table_name,
        message);
    return;
  }

  if (grn_table_columns(ctx, table, "", 0, (grn_obj *)columns) > 0) {
    GRN_HASH_EACH_BEGIN(ctx, columns, cursor, id)
    {
      void *key;
      if (grn_hash_cursor_get_key(ctx, cursor, &key) == 0) {
        continue;
      }

      if (data->is_close_opened_object_mode) {
        grn_ctx_push_temporary_open_space(ctx);
      }
      grn_id *column_id = key;
      grn_obj *column = grn_ctx_at(ctx, *column_id);
      if (column) {
        grn_obj_traverse_recursive_dispatch(ctx, data, column);
        grn_obj_unref(ctx, column);
      }
      if (data->is_close_opened_object_mode) {
        grn_ctx_pop_temporary_open_space(ctx);
      }

      if (ctx->rc != GRN_SUCCESS) {
        break;
      }
    }
    GRN_HASH_EACH_END(ctx, cursor);
  }
  grn_hash_close(ctx, columns);
  if (ctx->rc != GRN_SUCCESS) {
    return;
  }

  data->traverse(ctx, table, data->user_data);
}

static void
grn_obj_traverse_recursive_column(grn_ctx *ctx,
                                  grn_obj_traverse_recursive_data *data,
                                  grn_obj *column)
{
  data->traverse(ctx, column, data->user_data);
}

static void
grn_obj_traverse_recursive_dispatch(grn_ctx *ctx,
                                    grn_obj_traverse_recursive_data *data,
                                    grn_obj *obj)
{
  switch (obj->header.type) {
  case GRN_DB:
    grn_obj_traverse_recursive_db(ctx, data, obj);
    break;
  case GRN_TABLE_NO_KEY:
  case GRN_TABLE_HASH_KEY:
  case GRN_TABLE_PAT_KEY:
  case GRN_TABLE_DAT_KEY:
    grn_obj_traverse_recursive_table(ctx, data, obj);
    break;
  case GRN_COLUMN_FIX_SIZE:
  case GRN_COLUMN_VAR_SIZE:
  case GRN_COLUMN_INDEX:
    grn_obj_traverse_recursive_column(ctx, data, obj);
    break;
  default:
    {
      grn_obj inspected;
      GRN_TEXT_INIT(&inspected, 0);
      grn_inspect_limited(ctx, &inspected, obj);
      ERR(GRN_INVALID_ARGUMENT,
          "%s[recursive] "
          "object must be DB, table or column: %.*s",
          data->tag,
          (int)GRN_TEXT_LEN(&inspected),
          GRN_TEXT_VALUE(&inspected));
      GRN_OBJ_FIN(ctx, &inspected);
    }
    break;
  }
}

static void
grn_obj_traverse_recursive(grn_ctx *ctx,
                           grn_obj_traverse_recursive_data *data,
                           grn_obj *obj)
{
  data->is_close_opened_object_mode = (grn_thread_get_limit() == 1);
  grn_obj_traverse_recursive_dispatch(ctx, data, obj);
}

typedef struct {
  grn_hash *traversed;
  bool is_close_opened_object_mode;
  grn_obj *top_level_object;
  bool for_reference;
  grn_traverse_func *traverse;
  void *user_data;
  const char *tag;
} grn_obj_traverse_recursive_dependent_data;

static bool
grn_obj_traverse_recursive_dependent_need_traverse(
  grn_ctx *ctx, grn_obj_traverse_recursive_dependent_data *data, grn_id id)
{
  int added = 0;
  grn_id traversed_id =
    grn_hash_add(ctx, data->traversed, &id, sizeof(grn_id), NULL, &added);
  if (traversed_id == GRN_ID_NIL) {
    grn_rc rc = ctx->rc;
    if (rc == GRN_SUCCESS) {
      rc = GRN_NO_MEMORY_AVAILABLE;
    }
    char message[GRN_CTX_MSGSIZE];
    grn_strcpy(message, GRN_CTX_MSGSIZE, ctx->errbuf);
    ERR(rc,
        "%s[recursive][dependent] "
        "failed to register flushed ID: <%u>: %s",
        data->tag,
        id,
        message);
    return false;
  }
  return added != 0;
}

static void
grn_obj_traverse_recursive_dependent_dispatch(
  grn_ctx *ctx, grn_obj_traverse_recursive_dependent_data *data, grn_obj *obj);

static void
grn_obj_traverse_recursive_dependent_db(
  grn_ctx *ctx, grn_obj_traverse_recursive_dependent_data *data, grn_obj *db)
{
  GRN_TABLE_EACH_BEGIN(ctx, db, cursor, id)
  {
    if (!grn_obj_traverse_recursive_dependent_need_traverse(ctx, data, id)) {
      if (ctx->rc == GRN_SUCCESS) {
        continue;
      } else {
        break;
      }
    }

    if (data->is_close_opened_object_mode) {
      grn_ctx_push_temporary_open_space(ctx);
    }

    grn_obj *object = grn_ctx_at(ctx, id);
    if (grn_obj_is_table(ctx, object)) {
      data->top_level_object = object;
      grn_obj_traverse_recursive_dependent_dispatch(ctx, data, object);
    } else {
      if (ctx->rc != GRN_SUCCESS) {
        ERRCLR(ctx);
      }
    }
    if (object) {
      grn_obj_unref(ctx, object);
    }

    if (data->is_close_opened_object_mode) {
      grn_ctx_pop_temporary_open_space(ctx);
    }

    if (ctx->rc != GRN_SUCCESS) {
      break;
    }
  }
  GRN_TABLE_EACH_END(ctx, cursor);
  if (ctx->rc != GRN_SUCCESS) {
    return;
  }

  data->traverse(ctx, db, data->user_data);
}

static bool
grn_obj_traverse_recursive_dependent_table_is_target_column(
  grn_ctx *ctx,
  grn_obj_traverse_recursive_dependent_data *data,
  grn_obj *table,
  grn_obj *column)
{
  if (!data->for_reference) {
    return true;
  }

  if (table == data->top_level_object) {
    return true;
  }

  if (!grn_obj_is_index_column(ctx, column)) {
    return true;
  }

  if (grn_obj_is_table(ctx, data->top_level_object)) {
    return DB_OBJ(column)->range == DB_OBJ(data->top_level_object)->id;
  } else {
    if (DB_OBJ(column)->range != data->top_level_object->header.domain) {
      return false;
    }

    bool is_target = false;
    grn_obj source_ids;
    GRN_UINT32_INIT(&source_ids, GRN_OBJ_VECTOR);
    grn_obj_get_info(ctx, column, GRN_INFO_SOURCE, &source_ids);
    const size_t n = GRN_UINT32_VECTOR_SIZE(&source_ids);
    for (size_t i = 0; i < n; i++) {
      grn_id source_id = GRN_UINT32_VALUE_AT(&source_ids, i);
      if (source_id == DB_OBJ(data->top_level_object)->id) {
        is_target = true;
        break;
      }
    }
    GRN_OBJ_FIN(ctx, &source_ids);
    return is_target;
  }
}

static void
grn_obj_traverse_recursive_dependent_table(
  grn_ctx *ctx, grn_obj_traverse_recursive_dependent_data *data, grn_obj *table)
{
  if (grn_obj_is_table_with_key(ctx, table)) {
    grn_id domain_id = table->header.domain;
    if (grn_obj_traverse_recursive_dependent_need_traverse(ctx,
                                                           data,
                                                           domain_id)) {
      if (data->is_close_opened_object_mode) {
        grn_ctx_push_temporary_open_space(ctx);
      }
      grn_obj *domain = grn_ctx_at(ctx, domain_id);
      if (domain) {
        if (grn_obj_is_table(ctx, domain)) {
          grn_obj_traverse_recursive_dependent_dispatch(ctx, data, domain);
        }
        grn_obj_unref(ctx, domain);
      }
      if (data->is_close_opened_object_mode) {
        grn_ctx_pop_temporary_open_space(ctx);
      }
    }
    if (ctx->rc != GRN_SUCCESS) {
      return;
    }

    for (grn_hook *hooks = DB_OBJ(table)->hooks[GRN_HOOK_INSERT]; hooks;
         hooks = hooks->next) {
      grn_obj_default_set_value_hook_data *hook_data =
        (grn_obj_default_set_value_hook_data *)GRN_NEXT_ADDR(hooks);
      if (grn_obj_traverse_recursive_dependent_need_traverse(
            ctx,
            data,
            hook_data->target)) {
        if (data->is_close_opened_object_mode) {
          grn_ctx_push_temporary_open_space(ctx);
        }
        grn_obj *index = grn_ctx_at(ctx, hook_data->target);
        if (index) {
          grn_obj_traverse_recursive_dependent_dispatch(ctx, data, index);
          grn_obj_unref(ctx, index);
        }
        if (data->is_close_opened_object_mode) {
          grn_ctx_pop_temporary_open_space(ctx);
        }
        if (ctx->rc != GRN_SUCCESS) {
          return;
        }
      }
    }
  }

  if (data->for_reference || table == data->top_level_object) {
    grn_hash *columns = grn_hash_create(ctx,
                                        NULL,
                                        sizeof(grn_id),
                                        0,
                                        GRN_OBJ_TABLE_HASH_KEY | GRN_HASH_TINY);
    if (!columns) {
      grn_rc rc = ctx->rc;
      if (rc == GRN_SUCCESS) {
        rc = GRN_NO_MEMORY_AVAILABLE;
      }
      char message[GRN_CTX_MSGSIZE];
      grn_strcpy(message, GRN_CTX_MSGSIZE, ctx->errbuf);
      char table_name[GRN_TABLE_MAX_KEY_SIZE];
      int table_name_size;
      table_name_size =
        grn_obj_name(ctx, table, table_name, GRN_TABLE_MAX_KEY_SIZE);
      ERR(rc,
          "%s[recursive][dependent] "
          "failed to create internal hash table "
          "to store columns: <%.*s>: %s",
          data->tag,
          table_name_size,
          table_name,
          message);
      return;
    }

    if (grn_table_columns(ctx, table, "", 0, (grn_obj *)columns) > 0) {
      GRN_HASH_EACH_BEGIN(ctx, columns, cursor, id)
      {
        void *key;
        if (grn_hash_cursor_get_key(ctx, cursor, &key) == 0) {
          continue;
        }

        grn_id *column_id = key;
        if (!grn_obj_traverse_recursive_dependent_need_traverse(ctx,
                                                                data,
                                                                *column_id)) {
          if (ctx->rc == GRN_SUCCESS) {
            continue;
          } else {
            break;
          }
        }

        if (data->is_close_opened_object_mode) {
          grn_ctx_push_temporary_open_space(ctx);
        }
        grn_obj *column = grn_ctx_at(ctx, *column_id);
        if (column) {
          if (grn_obj_traverse_recursive_dependent_table_is_target_column(
                ctx,
                data,
                table,
                column)) {
            grn_obj_traverse_recursive_dependent_dispatch(ctx, data, column);
          }
          grn_obj_unref(ctx, column);
        }
        if (data->is_close_opened_object_mode) {
          grn_ctx_pop_temporary_open_space(ctx);
        }

        if (ctx->rc != GRN_SUCCESS) {
          break;
        }
      }
      GRN_HASH_EACH_END(ctx, cursor);
    }
    grn_hash_close(ctx, columns);
    if (ctx->rc != GRN_SUCCESS) {
      return;
    }
  }

  data->traverse(ctx, table, data->user_data);
}

static void
grn_obj_traverse_recursive_dependent_column_data(
  grn_ctx *ctx,
  grn_obj_traverse_recursive_dependent_data *data,
  grn_obj *column)
{
  if (column == data->top_level_object) {
    const grn_id table_id = column->header.domain;
    if (grn_obj_traverse_recursive_dependent_need_traverse(ctx,
                                                           data,
                                                           table_id)) {
      if (data->is_close_opened_object_mode) {
        grn_ctx_push_temporary_open_space(ctx);
      }
      grn_obj *table = grn_ctx_at(ctx, table_id);
      if (table) {
        grn_obj_traverse_recursive_dependent_dispatch(ctx, data, table);
        grn_obj_unref(ctx, table);
      }
      if (data->is_close_opened_object_mode) {
        grn_ctx_pop_temporary_open_space(ctx);
      }
    }
    if (ctx->rc != GRN_SUCCESS) {
      return;
    }
  }

  const grn_id range_id = grn_obj_get_range(ctx, column);
  if (grn_obj_traverse_recursive_dependent_need_traverse(ctx, data, range_id)) {
    if (data->is_close_opened_object_mode) {
      grn_ctx_push_temporary_open_space(ctx);
    }
    grn_obj *range = grn_ctx_at(ctx, range_id);
    if (range) {
      if (grn_obj_is_table(ctx, range)) {
        grn_obj_traverse_recursive_dependent_dispatch(ctx, data, range);
      }
      grn_obj_unref(ctx, range);
    }
    if (data->is_close_opened_object_mode) {
      grn_ctx_pop_temporary_open_space(ctx);
    }
  }
  if (ctx->rc != GRN_SUCCESS) {
    return;
  }

  for (grn_hook *hooks = DB_OBJ(column)->hooks[GRN_HOOK_SET]; hooks;
       hooks = hooks->next) {
    grn_obj_default_set_value_hook_data *hook_data =
      (grn_obj_default_set_value_hook_data *)GRN_NEXT_ADDR(hooks);
    if (grn_obj_traverse_recursive_dependent_need_traverse(ctx,
                                                           data,
                                                           hook_data->target)) {
      if (data->is_close_opened_object_mode) {
        grn_ctx_push_temporary_open_space(ctx);
      }
      grn_obj *index = grn_ctx_at(ctx, hook_data->target);
      if (index) {
        grn_obj_traverse_recursive_dependent_dispatch(ctx, data, index);
        grn_obj_unref(ctx, index);
      }
      if (data->is_close_opened_object_mode) {
        grn_ctx_pop_temporary_open_space(ctx);
      }
      if (ctx->rc != GRN_SUCCESS) {
        return;
      }
    }
  }

  data->traverse(ctx, column, data->user_data);
}

static void
grn_obj_traverse_recursive_dependent_column_index(
  grn_ctx *ctx,
  grn_obj_traverse_recursive_dependent_data *data,
  grn_obj *column)
{
  grn_id lexicon_id = column->header.domain;
  if (grn_obj_traverse_recursive_dependent_need_traverse(ctx,
                                                         data,
                                                         lexicon_id)) {
    if (data->is_close_opened_object_mode) {
      grn_ctx_push_temporary_open_space(ctx);
    }
    grn_obj *lexicon = grn_ctx_at(ctx, lexicon_id);
    if (lexicon) {
      grn_obj_traverse_recursive_dependent_dispatch(ctx, data, lexicon);
      grn_obj_unref(ctx, lexicon);
    }
    if (data->is_close_opened_object_mode) {
      grn_ctx_pop_temporary_open_space(ctx);
    }
  }
  if (ctx->rc != GRN_SUCCESS) {
    return;
  }

  grn_id range_id = DB_OBJ(column)->range;
  if (grn_obj_traverse_recursive_dependent_need_traverse(ctx, data, range_id)) {
    if (data->is_close_opened_object_mode) {
      grn_ctx_push_temporary_open_space(ctx);
    }
    grn_obj *source_table = grn_ctx_at(ctx, range_id);
    if (source_table) {
      grn_obj_traverse_recursive_dependent_dispatch(ctx, data, source_table);
      grn_obj_unref(ctx, source_table);
    }
    if (data->is_close_opened_object_mode) {
      grn_ctx_pop_temporary_open_space(ctx);
    }
  }
  if (ctx->rc != GRN_SUCCESS) {
    return;
  }

  grn_obj source_ids;
  GRN_UINT32_INIT(&source_ids, GRN_OBJ_VECTOR);
  grn_obj_get_info(ctx, column, GRN_INFO_SOURCE, &source_ids);
  const size_t n = GRN_UINT32_VECTOR_SIZE(&source_ids);
  for (size_t i = 0; i < n; i++) {
    grn_id source_id = GRN_UINT32_VALUE_AT(&source_ids, i);
    if (!grn_obj_traverse_recursive_dependent_need_traverse(ctx,
                                                            data,
                                                            source_id)) {
      if (ctx->rc == GRN_SUCCESS) {
        continue;
      } else {
        break;
      }
    }
    if (data->is_close_opened_object_mode) {
      grn_ctx_push_temporary_open_space(ctx);
    }
    grn_obj *source = grn_ctx_at(ctx, source_id);
    if (source) {
      grn_obj_traverse_recursive_dependent_dispatch(ctx, data, source);
      grn_obj_unref(ctx, source);
    }
    if (data->is_close_opened_object_mode) {
      grn_ctx_pop_temporary_open_space(ctx);
    }
    if (ctx->rc != GRN_SUCCESS) {
      break;
    }
  }
  GRN_OBJ_FIN(ctx, &source_ids);
  if (ctx->rc != GRN_SUCCESS) {
    return;
  }

  data->traverse(ctx, column, data->user_data);
}

static void
grn_obj_traverse_recursive_dependent_dispatch(
  grn_ctx *ctx, grn_obj_traverse_recursive_dependent_data *data, grn_obj *obj)
{
  switch (obj->header.type) {
  case GRN_DB:
    grn_obj_traverse_recursive_dependent_db(ctx, data, obj);
    break;
  case GRN_TABLE_NO_KEY:
  case GRN_TABLE_HASH_KEY:
  case GRN_TABLE_PAT_KEY:
  case GRN_TABLE_DAT_KEY:
    grn_obj_traverse_recursive_dependent_table(ctx, data, obj);
    break;
  case GRN_COLUMN_FIX_SIZE:
  case GRN_COLUMN_VAR_SIZE:
    grn_obj_traverse_recursive_dependent_column_data(ctx, data, obj);
    break;
  case GRN_COLUMN_INDEX:
    grn_obj_traverse_recursive_dependent_column_index(ctx, data, obj);
    break;
  default:
    {
      grn_obj inspected;
      GRN_TEXT_INIT(&inspected, 0);
      grn_inspect_limited(ctx, &inspected, obj);
      ERR(GRN_INVALID_ARGUMENT,
          "%s[recursive][dependent] "
          "object must be DB, table or column: %.*s",
          data->tag,
          (int)GRN_TEXT_LEN(&inspected),
          GRN_TEXT_VALUE(&inspected));
      GRN_OBJ_FIN(ctx, &inspected);
    }
    break;
  }
}

static void
grn_obj_traverse_recursive_dependent(
  grn_ctx *ctx, grn_obj_traverse_recursive_dependent_data *data, grn_obj *obj)
{
  data->traversed = grn_hash_create(ctx,
                                    NULL,
                                    sizeof(grn_id),
                                    0,
                                    GRN_OBJ_TABLE_HASH_KEY | GRN_HASH_TINY);
  if (!data->traversed) {
    grn_rc rc = ctx->rc;
    if (rc == GRN_SUCCESS) {
      rc = GRN_NO_MEMORY_AVAILABLE;
    }
    char message[GRN_CTX_MSGSIZE];
    grn_strcpy(message, GRN_CTX_MSGSIZE, ctx->errbuf);
    char name[GRN_TABLE_MAX_KEY_SIZE];
    int name_size;
    name_size = grn_obj_name(ctx, obj, name, GRN_TABLE_MAX_KEY_SIZE);
    ERR(rc,
        "%s[recursive][dependent] "
        "failed to create an internal hash table "
        "to manage traversed objects: <%.*s>: %s",
        data->tag,
        name_size,
        name,
        message);
    return;
  }

  data->is_close_opened_object_mode = (grn_thread_get_limit() == 1);

  grn_id id = grn_obj_id(ctx, obj);
  if (grn_obj_traverse_recursive_dependent_need_traverse(ctx, data, id)) {
    data->top_level_object = obj;
    grn_obj_traverse_recursive_dependent_dispatch(ctx, data, obj);
  }

  grn_hash_close(ctx, data->traversed);
}

static void
grn_table_close_columns(grn_ctx *ctx, grn_obj *table)
{
  grn_hash *columns;
  int n_columns;

  columns = grn_hash_create(ctx,
                            NULL,
                            sizeof(grn_id),
                            0,
                            GRN_OBJ_TABLE_HASH_KEY | GRN_HASH_TINY);
  if (!columns) {
    return;
  }

  n_columns = grn_table_columns(ctx, table, "", 0, (grn_obj *)columns);
  if (n_columns > 0) {
    grn_hash_cursor *cursor;
    cursor = grn_hash_cursor_open(ctx, columns, NULL, 0, NULL, 0, 0, -1, 0);
    if (cursor) {
      while (grn_hash_cursor_next(ctx, cursor) != GRN_ID_NIL) {
        grn_id *id;
        grn_obj *column;

        grn_hash_cursor_get_key(ctx, cursor, (void **)&id);
        column = grn_ctx_at(ctx, *id);
        if (column) {
          grn_obj_close(ctx, column);
        }
      }
      grn_hash_cursor_close(ctx, cursor);
    }
  }

  grn_hash_close(ctx, columns);
}

grn_rc
grn_obj_close(grn_ctx *ctx, grn_obj *obj)
{
  if (!obj) {
    return GRN_SUCCESS;
  }

  GRN_API_ENTER;
  if (GRN_DB_OBJP(obj)) {
    grn_id id = DB_OBJ(obj)->id;
    grn_obj *db = DB_OBJ(obj)->db;
    grn_hook_entry entry;

    grn_log_reference_count("%p: close: %u: %p\n", ctx, id, obj);

    if (id != GRN_ID_NIL && !(id & GRN_OBJ_TMP_OBJECT) && db) {
      grn_db_remove_deferred_unref(ctx, db, id);
      if (grn_reference_count_should_log(ctx, obj->header.type)) {
        const char *name;
        uint32_t name_size = 0;
        name = _grn_table_key(ctx, db, id, &name_size);
        GRN_LOG(ctx,
                GRN_LOG_REFERENCE_COUNT,
                "[obj][close] <%u>(<%.*s>):<%u>(<%s>)",
                id,
                name_size,
                name,
                obj->header.type,
                grn_obj_type_to_string(obj->header.type));
      }
    }

    if (grn_obj_is_table(ctx, obj) && (id & GRN_OBJ_TMP_OBJECT)) {
      grn_table_close_columns(ctx, obj);
    }
    if (DB_OBJ(obj)->finalizer) {
      DB_OBJ(obj)->finalizer(ctx, 1, &obj, &DB_OBJ(obj)->user_data);
    }
    if (DB_OBJ(obj)->source) {
      GRN_FREE(DB_OBJ(obj)->source);
    }
    for (entry = 0; entry < GRN_N_HOOK_ENTRIES; entry++) {
      grn_hook_free(ctx, DB_OBJ(obj)->hooks[entry]);
    }
    if (id & GRN_OBJ_TMP_OBJECT) {
      grn_obj_clear_option_values(ctx, obj);
      if (grn_obj_is_table(ctx, obj)) {
        grn_ctx_impl_columns_cache_delete(ctx, id);
      } else if (grn_obj_is_column(ctx, obj)) {
        grn_ctx_impl_columns_cache_delete(ctx, obj->header.domain);
      }
    }
    grn_obj_delete_by_id(ctx, DB_OBJ(obj)->db, id, GRN_FALSE);
  }
  switch (obj->header.type) {
  case GRN_VECTOR:
    if (obj->u.v.body && !(obj->header.impl_flags & GRN_OBJ_REFER)) {
      grn_obj_close(ctx, obj->u.v.body);
    }
    if (obj->u.v.sections) {
      GRN_FREE(obj->u.v.sections);
    }
    if (obj->header.impl_flags & GRN_OBJ_ALLOCATED) {
      GRN_FREE(obj);
    }
    GRN_API_RETURN(GRN_SUCCESS);
  case GRN_VOID:
  case GRN_BULK:
  case GRN_UVECTOR:
  case GRN_MSG:
    {
      obj->header.type = GRN_VOID;
      bool is_allocated = (obj->header.impl_flags & GRN_OBJ_ALLOCATED);
      grn_rc rc = grn_bulk_fin(ctx, obj);
      if (is_allocated) {
        GRN_FREE(obj);
      }
      GRN_API_RETURN(rc);
    }
  case GRN_PTR:
    {
      if (obj->header.impl_flags & GRN_OBJ_OWN) {
        if (GRN_BULK_VSIZE(obj) == sizeof(grn_obj *)) {
          grn_obj_close(ctx, GRN_PTR_VALUE(obj));
        }
      }
      obj->header.type = GRN_VOID;
      bool is_allocated = (obj->header.impl_flags & GRN_OBJ_ALLOCATED);
      grn_rc rc = grn_bulk_fin(ctx, obj);
      if (is_allocated) {
        GRN_FREE(obj);
      }
      GRN_API_RETURN(rc);
    }
  case GRN_PVECTOR:
    {
      grn_rc rc = grn_pvector_fin(ctx, obj);
      GRN_API_RETURN(rc);
    }
  case GRN_ACCESSOR:
    {
      grn_accessor *p, *n;
      for (p = (grn_accessor *)obj; p; p = n) {
        grn_obj_unref(ctx, p->obj);
        n = p->next;
        GRN_FREE(p);
      }
    }
    GRN_API_RETURN(GRN_SUCCESS);
  case GRN_SNIP:
    {
      grn_rc rc = grn_snip_close(ctx, (grn_snip *)obj);
      GRN_API_RETURN(rc);
    }
  case GRN_STRING:
    {
      grn_rc rc = grn_string_close(ctx, obj);
      GRN_API_RETURN(rc);
    }
  case GRN_HIGHLIGHTER:
    {
      grn_rc rc = grn_highlighter_close(ctx, (grn_highlighter *)obj);
      GRN_API_RETURN(rc);
    }
  case GRN_CURSOR_TABLE_PAT_KEY:
    grn_pat_cursor_close(ctx, (grn_pat_cursor *)obj);
    GRN_API_RETURN(GRN_SUCCESS);
  case GRN_CURSOR_TABLE_DAT_KEY:
    grn_dat_cursor_close(ctx, (grn_dat_cursor *)obj);
    GRN_API_RETURN(GRN_SUCCESS);
  case GRN_CURSOR_TABLE_HASH_KEY:
    grn_hash_cursor_close(ctx, (grn_hash_cursor *)obj);
    GRN_API_RETURN(GRN_SUCCESS);
  case GRN_CURSOR_TABLE_NO_KEY:
    grn_array_cursor_close(ctx, (grn_array_cursor *)obj);
    GRN_API_RETURN(GRN_SUCCESS);
  case GRN_CURSOR_COLUMN_INDEX:
    grn_index_cursor_close(ctx, obj);
    GRN_API_RETURN(GRN_SUCCESS);
  case GRN_CURSOR_COLUMN_GEO_INDEX:
    grn_geo_cursor_close(ctx, obj);
    GRN_API_RETURN(GRN_SUCCESS);
  case GRN_CURSOR_CONFIG:
    grn_config_cursor_close(ctx, (grn_config_cursor *)obj);
    GRN_API_RETURN(GRN_SUCCESS);
  case GRN_TYPE:
    GRN_FREE(obj);
    GRN_API_RETURN(GRN_SUCCESS);
  case GRN_DB:
    {
      grn_rc rc = grn_db_close(ctx, obj);
      GRN_API_RETURN(rc);
    }
  case GRN_TABLE_PAT_KEY:
    {
      grn_rc rc = grn_pat_close(ctx, (grn_pat *)obj);
      GRN_API_RETURN(rc);
    }
  case GRN_TABLE_DAT_KEY:
    {
      grn_rc rc = grn_dat_close(ctx, (grn_dat *)obj);
      GRN_API_RETURN(rc);
    }
  case GRN_TABLE_HASH_KEY:
    {
      grn_rc rc = grn_hash_close(ctx, (grn_hash *)obj);
      GRN_API_RETURN(rc);
    }
  case GRN_TABLE_NO_KEY:
    {
      grn_rc rc = grn_array_close(ctx, (grn_array *)obj);
      GRN_API_RETURN(rc);
    }
  case GRN_COLUMN_VAR_SIZE:
    {
      grn_rc rc = grn_ja_close(ctx, (grn_ja *)obj);
      GRN_API_RETURN(rc);
    }
  case GRN_COLUMN_FIX_SIZE:
    {
      grn_rc rc = grn_ra_close(ctx, (grn_ra *)obj);
      GRN_API_RETURN(rc);
    }
  case GRN_COLUMN_INDEX:
    {
      grn_rc rc = grn_ii_close(ctx, (grn_ii *)obj);
      GRN_API_RETURN(rc);
    }
  case GRN_PROC:
    {
      uint32_t i;
      grn_proc *p = (grn_proc *)obj;
      /*
        if (obj->header.domain) {
          grn_hash_delete(ctx, ctx->impl->qe, &obj->header.domain,
          sizeof(grn_id), NULL);
        }
      */
      for (i = 0; i < p->nvars; i++) {
        grn_obj_close(ctx, &p->vars[i].value);
      }
      GRN_REALLOC(p->vars, 0);
      grn_obj_close(ctx, &p->name_buf);
      if (p->obj.range != GRN_ID_NIL) {
        grn_plugin_close(ctx, p->obj.range);
      }
      GRN_FREE(obj);
    }
    GRN_API_RETURN(GRN_SUCCESS);
  case GRN_EXPR:
    {
      grn_rc rc = grn_expr_close(ctx, obj);
      GRN_API_RETURN(rc);
    }
  default:
    GRN_API_RETURN(GRN_SUCCESS);
  }
}

grn_rc
grn_obj_unlink(grn_ctx *ctx, grn_obj *obj)
{
  if (!obj) {
    return GRN_SUCCESS;
  }

  if (obj->header.type == GRN_DB) {
    return grn_obj_close(ctx, obj);
  }

  if (obj->header.type == GRN_ACCESSOR) {
    if (grn_enable_reference_count) {
      grn_accessor *accessor = (grn_accessor *)obj;
      GRN_API_ENTER;
      grn_log_reference_count("%p: unlink: start: accessor: %p: %u\n",
                              ctx,
                              obj,
                              accessor->reference_count);
      accessor->reference_count--;
      uint32_t current_reference_count = accessor->reference_count;
      grn_rc rc = GRN_SUCCESS;
      if (current_reference_count == 0) {
        rc = grn_obj_close(ctx, obj);
      }
      grn_log_reference_count("%p: unlink: done: accessor: %p: %u\n",
                              ctx,
                              obj,
                              current_reference_count);
      GRN_API_RETURN(rc);
    } else {
      return grn_obj_close(ctx, obj);
    }
  }

  if (!GRN_DB_OBJP(obj)) {
    return grn_obj_close(ctx, obj);
  }

  grn_db_obj *db_obj = DB_OBJ(obj);
  grn_id id = db_obj->id;

  if (id == GRN_ID_NIL || (id & GRN_OBJ_TMP_OBJECT)) {
    if (grn_enable_reference_count) {
      GRN_API_ENTER;
      grn_log_reference_count("%p: unlink: start: %u: %p: %u\n",
                              ctx,
                              id,
                              obj,
                              db_obj->reference_count);
      db_obj->reference_count--;
      uint32_t current_reference_count = db_obj->reference_count;
      grn_rc rc = GRN_SUCCESS;
      if (current_reference_count == 0) {
        rc = grn_obj_close(ctx, obj);
      }
      grn_log_reference_count("%p: unlink: done: %u: %p: %u\n",
                              ctx,
                              id,
                              obj,
                              current_reference_count);
      GRN_API_RETURN(rc);
    } else {
      return grn_obj_close(ctx, obj);
    }
  }

  /* Don't unlink built-in objects. We must update the same condition
   * in grn_ctx_at() when we need to unlink built-in objects. */
  if (id < GRN_N_RESERVED_TYPES) {
    return GRN_SUCCESS;
  }

  if (!grn_enable_reference_count) {
    return GRN_SUCCESS;
  }

  GRN_API_ENTER;
  grn_db *s = (grn_db *)(db_obj->db);
  db_value *vp = grn_tiny_array_at(&s->values, id);
  if (vp) {
    grn_log_reference_count("%p: unlink: start: %u: %p: %u: %p\n",
                            ctx,
                            id,
                            obj,
                            vp->lock,
                            vp->ptr);
    if (vp->lock == 0) {
      grn_log_reference_count("%p: unlink: done: not referenced: "
                              "%u: %p: %u: %p\n",
                              ctx,
                              id,
                              obj,
                              vp->lock,
                              vp->ptr);
      ERR(GRN_INVALID_ARGUMENT,
          "[obj][unlink] not referenced object: "
          "id:<%u> "
          "obj:<%p> "
          "lock:<%u> "
          "address:<%p>",
          id,
          obj,
          vp->lock,
          vp->ptr);
      GRN_API_RETURN(ctx->rc);
    }
    uint32_t current_lock;
    uint32_t *lock_pointer = &vp->lock;
    GRN_ATOMIC_ADD_EX(lock_pointer, -1, current_lock);
#ifdef GRN_REFERENCE_COUNT_DEBUG
    uint32_t current_reference_count = vp->lock;
#endif
    if (current_lock == 1) {
      grn_log_reference_count("%p: unlink: lock: %u: %p: %u: %u\n",
                              ctx,
                              id,
                              obj,
                              current_lock,
                              current_reference_count);
      GRN_ATOMIC_ADD_EX(lock_pointer, GRN_IO_MAX_REF, current_lock);
      uint32_t reset_max_ref_by_overflow = GRN_IO_MAX_REF - 1;
#ifdef GRN_REFERENCE_COUNT_DEBUG
      current_reference_count = vp->lock;
#endif
      grn_log_reference_count("%p: unlink: locked: %u: %p: %u: %u\n",
                              ctx,
                              id,
                              obj,
                              current_lock,
                              current_reference_count);
      if (current_lock == 0) {
        grn_rc rc = grn_obj_close(ctx, obj);
        grn_log_reference_count("%p: unlink: done: %u: %p: %u\n",
                                ctx,
                                id,
                                obj,
                                current_reference_count);
        GRN_API_RETURN(rc);
      } else {
        grn_log_reference_count("%p: unlink: unlock: %u: %p: %u: %u\n",
                                ctx,
                                id,
                                obj,
                                current_lock,
                                current_reference_count);
        GRN_ATOMIC_ADD_EX(lock_pointer,
                          reset_max_ref_by_overflow,
                          current_lock);
#ifdef GRN_REFERENCE_COUNT_DEBUG
        current_reference_count = vp->lock;
#endif
        grn_log_reference_count("%p: unlink: unlocked: %u: %p: %u: %u\n",
                                ctx,
                                id,
                                obj,
                                current_lock,
                                current_reference_count);
      }
      GRN_FUTEX_WAKE(lock_pointer);
    }
    grn_log_reference_count("%p: unlink: done: %u: %p: %u\n",
                            ctx,
                            id,
                            obj,
                            current_reference_count);
    GRN_API_RETURN(GRN_SUCCESS);
  }
  GRN_API_RETURN(GRN_SUCCESS);
}

void
grn_obj_unref(grn_ctx *ctx, grn_obj *obj)
{
  if (!grn_enable_reference_count) {
    return;
  }

  grn_obj_unlink(ctx, obj);
}

static void
grn_obj_unref_traverse(grn_ctx *ctx, grn_obj *obj, void *user_data)
{
  if (obj->header.type == GRN_DB) {
    return;
  }
  grn_obj_unref(ctx, obj);
}

void
grn_obj_unref_recursive(grn_ctx *ctx, grn_obj *obj)
{
  if (!grn_enable_reference_count) {
    return;
  }

  GRN_API_ENTER;

  grn_obj_traverse_recursive_data data;
  data.tag = "[obj][unref]";
  data.traverse = grn_obj_unref_traverse;
  data.user_data = NULL;
  grn_obj_traverse_recursive(ctx, &data, obj);

  GRN_API_RETURN();
}

void
grn_obj_unref_recursive_dependent(grn_ctx *ctx, grn_obj *obj)
{
  if (!grn_enable_reference_count) {
    return;
  }

  GRN_API_ENTER;

  grn_obj_traverse_recursive_dependent_data data;
  data.tag = "[obj][unref]";
  data.traverse = grn_obj_unref_traverse;
  data.user_data = NULL;
  data.for_reference = true;
  grn_obj_traverse_recursive_dependent(ctx, &data, obj);

  GRN_API_RETURN();
}

static grn_rc
grn_obj_refer_record(grn_ctx *ctx, grn_obj *obj, grn_obj *ids)
{
  if (!grn_enable_reference_count) {
    return ctx->rc;
  }

  if (!obj) {
    return ctx->rc;
  }

  if (grn_obj_is_accessor(ctx, obj)) {
    grn_accessor_refer(ctx, obj);
    return ctx->rc;
  }

  if (GRN_DB_OBJP(obj)) {
    grn_id id = grn_obj_id(ctx, obj);
    if (grn_ctx_at(ctx, id) && ids) {
      GRN_RECORD_PUT(ctx, ids, id);
    }
    return ctx->rc;
  }

  return ctx->rc;
}

grn_rc
grn_obj_refer_auto_release(grn_ctx *ctx, grn_obj *obj, uint32_t count)
{
  if (!grn_enable_reference_count) {
    return ctx->rc;
  }

  if (count > 0) {
    grn_deferred_unref deferred_unref;
    deferred_unref.count = count;
    GRN_RECORD_INIT(&(deferred_unref.ids), GRN_OBJ_VECTOR, GRN_ID_NIL);
    grn_obj_refer_record(ctx, obj, &(deferred_unref.ids));
    if (ctx->rc == GRN_SUCCESS) {
      grn_db_add_deferred_unref(ctx, grn_ctx_db(ctx), &deferred_unref);
    }
    GRN_OBJ_FIN(ctx, &(deferred_unref.ids));
    return ctx->rc;
  } else {
    return grn_obj_refer_record(ctx, obj, NULL);
  }
}

grn_rc
grn_obj_refer(grn_ctx *ctx, grn_obj *obj)
{
  return grn_obj_refer_auto_release(ctx, obj, 0);
}

static void
grn_obj_refer_traverse(grn_ctx *ctx, grn_obj *obj, void *user_data)
{
  if (obj->header.type == GRN_DB) {
    return;
  }
  grn_deferred_unref *deferred_unref = user_data;
  if (deferred_unref->count == 0) {
    grn_obj_refer(ctx, obj);
  } else {
    grn_obj_refer_record(ctx, obj, &(deferred_unref->ids));
  }
}

grn_rc
grn_obj_refer_recursive_auto_release(grn_ctx *ctx, grn_obj *obj, uint32_t count)
{
  if (!grn_enable_reference_count) {
    return ctx->rc;
  }

  GRN_API_ENTER;

  grn_deferred_unref deferred_unref;
  deferred_unref.count = count;
  GRN_RECORD_INIT(&(deferred_unref.ids), GRN_OBJ_VECTOR, GRN_ID_NIL);
  grn_obj_traverse_recursive_data data;
  data.tag = "[obj][refer]";
  data.traverse = grn_obj_refer_traverse;
  data.user_data = &deferred_unref;
  grn_obj_traverse_recursive(ctx, &data, obj);
  if (ctx->rc == GRN_SUCCESS && deferred_unref.count > 0) {
    grn_db_add_deferred_unref(ctx, grn_ctx_db(ctx), &deferred_unref);
  }
  GRN_OBJ_FIN(ctx, &(deferred_unref.ids));

  GRN_API_RETURN(ctx->rc);
}

grn_rc
grn_obj_refer_recursive(grn_ctx *ctx, grn_obj *obj)
{
  return grn_obj_refer_recursive_auto_release(ctx, obj, 0);
}

grn_rc
grn_obj_refer_recursive_dependent_auto_release(grn_ctx *ctx,
                                               grn_obj *obj,
                                               uint32_t count)
{
  if (!grn_enable_reference_count) {
    return ctx->rc;
  }

  GRN_API_ENTER;

  grn_deferred_unref deferred_unref;
  deferred_unref.count = count;
  GRN_RECORD_INIT(&(deferred_unref.ids), GRN_OBJ_VECTOR, GRN_ID_NIL);
  grn_obj_traverse_recursive_dependent_data data;
  data.tag = "[obj][refer]";
  data.traverse = grn_obj_refer_traverse;
  data.user_data = &deferred_unref;
  data.for_reference = true;
  grn_obj_traverse_recursive_dependent(ctx, &data, obj);
  if (ctx->rc == GRN_SUCCESS && deferred_unref.count > 0) {
    grn_db_add_deferred_unref(ctx, grn_ctx_db(ctx), &deferred_unref);
  }
  GRN_OBJ_FIN(ctx, &(deferred_unref.ids));

  GRN_API_RETURN(ctx->rc);
}

grn_rc
grn_obj_refer_recursive_dependent(grn_ctx *ctx, grn_obj *obj)
{
  return grn_obj_refer_recursive_dependent_auto_release(ctx, obj, 0);
}

/* Internal function for debug */
uint32_t
grn_obj_reference_count(grn_ctx *ctx, grn_obj *obj)
{
  if (!obj) {
    return 0;
  }

  if (obj->header.type == GRN_DB) {
    return 0;
  }

  if (obj->header.type == GRN_ACCESSOR) {
    grn_accessor *accessor = (grn_accessor *)obj;
    return accessor->reference_count;
  }

  if (!GRN_DB_OBJP(obj)) {
    return 0;
  }

  grn_db_obj *db_obj = DB_OBJ(obj);
  grn_id id = db_obj->id;

  if (id == GRN_ID_NIL || (id & GRN_OBJ_TMP_OBJECT)) {
    return db_obj->reference_count;
  }

  grn_db *s = (grn_db *)(db_obj->db);
  db_value *vp = grn_tiny_array_at(&s->values, id);
  if (vp) {
    return vp->lock;
  } else {
    return 0;
  }
}

static inline void
grn_vector_clear(grn_ctx *ctx, grn_obj *obj)
{
  if (obj->u.v.body && !(obj->header.impl_flags & GRN_OBJ_REFER)) {
    grn_obj_close(ctx, obj->u.v.body);
  }
  if (obj->u.v.sections) {
    GRN_FREE(obj->u.v.sections);
  }
  obj->header.impl_flags &= ~GRN_OBJ_DO_SHALLOW_COPY;
  memset(&(obj->u), 0, sizeof(obj->u));
}

void
grn_obj_ensure_vector(grn_ctx *ctx, grn_obj *obj)
{
  if (obj->header.type != GRN_VECTOR) {
    grn_bulk_fin(ctx, obj);
  }
  obj->header.type = GRN_VECTOR;
  obj->header.flags &= ~GRN_OBJ_WITH_WEIGHT;
}

void
grn_obj_ensure_bulk(grn_ctx *ctx, grn_obj *obj)
{
  if (obj->header.type == GRN_VECTOR) {
    grn_vector_clear(ctx, obj);
  }
  obj->header.type = GRN_BULK;
  obj->header.flags &= ~GRN_OBJ_WITH_WEIGHT;
}

grn_rc
grn_obj_reinit(grn_ctx *ctx, grn_obj *obj, grn_id domain, uint8_t flags)
{
  if (!GRN_OBJ_MUTABLE(obj)) {
    ERR(GRN_INVALID_ARGUMENT, "invalid obj assigned");
  } else {
    switch (obj->header.type) {
    case GRN_PTR:
      if (obj->header.impl_flags & GRN_OBJ_OWN) {
        if (GRN_BULK_VSIZE(obj) == sizeof(grn_obj *)) {
          grn_obj_close(ctx, GRN_PTR_VALUE(obj));
        }
        obj->header.impl_flags &= ~GRN_OBJ_OWN;
      }
      break;
    case GRN_PVECTOR:
      if (obj->header.impl_flags & GRN_OBJ_OWN) {
        unsigned int i, n_elements;
        n_elements = GRN_BULK_VSIZE(obj) / sizeof(grn_obj *);
        for (i = 0; i < n_elements; i++) {
          grn_obj *element = GRN_PTR_VALUE_AT(obj, i);
          grn_obj_close(ctx, element);
        }
        obj->header.impl_flags &= ~GRN_OBJ_OWN;
      }
      break;
    default:
      break;
    }

    switch (domain) {
    case GRN_DB_VOID:
      obj->header.domain = domain;
      if (flags & GRN_OBJ_VECTOR) {
        if (obj->header.type == GRN_VECTOR) {
          grn_vector_clear(ctx, obj);
        } else {
          grn_bulk_fin(ctx, obj);
          obj->header.type = GRN_VECTOR;
          if (obj->u.v.body) {
            if (obj->header.impl_flags & GRN_OBJ_DO_SHALLOW_COPY) {
              obj->u.v.body = NULL;
              obj->header.impl_flags &= ~GRN_OBJ_DO_SHALLOW_COPY;
            } else {
              grn_obj_reinit(ctx, obj->u.v.body, domain, 0);
            }
          }
          obj->u.v.n_sections = 0;
        }
      } else {
        if (obj->header.type == GRN_VECTOR) {
          grn_vector_clear(ctx, obj);
        }
        obj->header.type = GRN_VOID;
      }
      GRN_BULK_REWIND(obj);
      break;
    case GRN_DB_OBJECT:
    case GRN_DB_BOOL:
    case GRN_DB_INT8:
    case GRN_DB_UINT8:
    case GRN_DB_INT16:
    case GRN_DB_UINT16:
    case GRN_DB_INT32:
    case GRN_DB_UINT32:
    case GRN_DB_INT64:
    case GRN_DB_UINT64:
    case GRN_DB_BFLOAT16:
    case GRN_DB_FLOAT32:
    case GRN_DB_FLOAT:
    case GRN_DB_TIME:
    case GRN_DB_TOKYO_GEO_POINT:
    case GRN_DB_WGS84_GEO_POINT:
      if (obj->header.type == GRN_VECTOR) {
        grn_vector_clear(ctx, obj);
      }
      obj->header.type = (flags & GRN_OBJ_VECTOR) ? GRN_UVECTOR : GRN_BULK;
      obj->header.domain = domain;
      GRN_BULK_REWIND(obj);
      break;
    case GRN_DB_SHORT_TEXT:
    case GRN_DB_TEXT:
    case GRN_DB_LONG_TEXT:
      if (flags & GRN_OBJ_VECTOR) {
        if (obj->header.type != GRN_VECTOR) {
          grn_bulk_fin(ctx, obj);
        }
        obj->header.type = GRN_VECTOR;
        if (obj->u.v.body) {
          if (obj->header.impl_flags & GRN_OBJ_DO_SHALLOW_COPY) {
            obj->u.v.body = NULL;
            obj->header.impl_flags &= ~GRN_OBJ_DO_SHALLOW_COPY;
          } else {
            grn_obj_reinit(ctx, obj->u.v.body, domain, 0);
          }
        }
        obj->u.v.n_sections = 0;
      } else {
        if (obj->header.type == GRN_VECTOR) {
          grn_vector_clear(ctx, obj);
        }
        obj->header.type = GRN_BULK;
      }
      obj->header.domain = domain;
      GRN_BULK_REWIND(obj);
      break;
    default:
      if (grn_type_id_is_text_family(ctx, domain)) {
        if (flags & GRN_OBJ_VECTOR) {
          if (obj->header.type != GRN_VECTOR) {
            grn_bulk_fin(ctx, obj);
          }
          obj->header.type = GRN_VECTOR;
        } else {
          if (obj->header.type == GRN_VECTOR) {
            grn_vector_clear(ctx, obj);
          }
          obj->header.type = GRN_BULK;
        }
      } else {
        if (obj->header.type == GRN_VECTOR) {
          grn_vector_clear(ctx, obj);
        }
        obj->header.type = (flags & GRN_OBJ_VECTOR) ? GRN_UVECTOR : GRN_BULK;
      }
      obj->header.domain = domain;
      GRN_BULK_REWIND(obj);
      break;
    }
  }
  return ctx->rc;
}

grn_rc
grn_obj_reinit_for(grn_ctx *ctx, grn_obj *obj, grn_obj *domain_obj)
{
  grn_id domain = GRN_ID_NIL;
  grn_obj_flags flags = 0;

  if (!GRN_DB_OBJP(domain_obj) && domain_obj->header.type != GRN_ACCESSOR) {
    grn_obj inspected;
    GRN_TEXT_INIT(&inspected, 0);
    grn_inspect_limited(ctx, &inspected, domain_obj);
    ERR(GRN_INVALID_ARGUMENT,
        "[reinit] invalid domain object: <%.*s>",
        (int)GRN_TEXT_LEN(&inspected),
        GRN_TEXT_VALUE(&inspected));
    GRN_OBJ_FIN(ctx, &inspected);
    return ctx->rc;
  }

  if (grn_column_is_index(ctx, domain_obj)) {
    domain = GRN_DB_UINT32;
  } else {
    grn_obj_get_range_info(ctx, domain_obj, &domain, &flags);
    if (GRN_OBJ_TABLEP(domain_obj) &&
        domain_obj->header.type != GRN_TABLE_NO_KEY) {
      domain = domain_obj->header.domain;
    }
  }
  uint8_t reinit_flags =
    (uint8_t)(flags & (GRN_OBJ_VECTOR | GRN_OBJ_DO_SHALLOW_COPY));
  return grn_obj_reinit(ctx, obj, domain, reinit_flags);
}

const char *
grn_obj_path(grn_ctx *ctx, grn_obj *obj)
{
  grn_io *io;
  const char *path = NULL;
  GRN_API_ENTER;
  if (obj->header.type == GRN_PROC) {
    path = grn_plugin_path(ctx, DB_OBJ(obj)->range);
    GRN_API_RETURN(path);
  }
  io = grn_obj_get_io(ctx, obj);
  if (io && !(io->flags & GRN_IO_TEMPORARY)) {
    path = io->path;
  }
  GRN_API_RETURN(path);
}

int
grn_obj_name(grn_ctx *ctx, grn_obj *obj, char *namebuf, int buf_size)
{
  int len = 0;
  GRN_API_ENTER;
  if (GRN_DB_OBJP(obj)) {
    if (DB_OBJ(obj)->id) {
      grn_db *s = (grn_db *)DB_OBJ(obj)->db;
      grn_id id = DB_OBJ(obj)->id;
      if (id & GRN_OBJ_TMP_OBJECT) {
        if (id & GRN_OBJ_TMP_COLUMN) {
          grn_id real_id = id & ~(GRN_OBJ_TMP_OBJECT | GRN_OBJ_TMP_COLUMN);
          grn_ctx *target_ctx = ctx;
          while (target_ctx->impl->parent) {
            target_ctx = target_ctx->impl->parent;
          }
          len = grn_pat_get_key(target_ctx,
                                target_ctx->impl->temporary_columns,
                                real_id,
                                namebuf,
                                buf_size);
        }
      } else {
        len = grn_table_get_key(ctx, s->keys, id, namebuf, buf_size);
      }
    }
  }
  GRN_API_RETURN(len);
}

int
grn_column_name(grn_ctx *ctx, grn_obj *obj, char *namebuf, int buf_size)
{
  int len = 0;
  char buf[GRN_TABLE_MAX_KEY_SIZE];
  if (!obj) {
    return len;
  }
  GRN_API_ENTER;
  if (GRN_DB_OBJP(obj)) {
    grn_id id = DB_OBJ(obj)->id;
    if (id & GRN_OBJ_TMP_OBJECT) {
      if (id & GRN_OBJ_TMP_COLUMN) {
        grn_id real_id = id & ~(GRN_OBJ_TMP_OBJECT | GRN_OBJ_TMP_COLUMN);
        grn_ctx *target_ctx = ctx;
        while (target_ctx->impl->parent) {
          target_ctx = target_ctx->impl->parent;
        }
        len = grn_pat_get_key(target_ctx,
                              target_ctx->impl->temporary_columns,
                              real_id,
                              buf,
                              GRN_TABLE_MAX_KEY_SIZE);
      }
    } else if (id && id < GRN_ID_MAX) {
      grn_db *s = (grn_db *)DB_OBJ(obj)->db;
      len = grn_table_get_key(ctx, s->keys, id, buf, GRN_TABLE_MAX_KEY_SIZE);
    }
    if (len) {
      int cl;
      char *p = buf, *p0 = p, *pe = p + len;
      for (; p < pe && (cl = grn_charlen(ctx, p, pe)); p += cl) {
        if (*p == GRN_DB_DELIMITER && cl == 1) {
          p0 = p + cl;
        }
      }
      len = pe - p0;
      if (len && len <= buf_size) {
        grn_memcpy(namebuf, p0, len);
      }
    }
  } else if (obj->header.type == GRN_ACCESSOR) {
    grn_obj name;
    grn_accessor *a;

    GRN_TEXT_INIT(&name, 0);

#define ADD_DELMITER()                                                         \
  do {                                                                         \
    if (GRN_TEXT_LEN(&name) > 0) {                                             \
      GRN_TEXT_PUTC(ctx, &name, GRN_DB_DELIMITER);                             \
    }                                                                          \
  } while (GRN_FALSE)

    for (a = (grn_accessor *)obj; a; a = a->next) {
      switch (a->action) {
      case GRN_ACCESSOR_GET_ID:
        ADD_DELMITER();
        GRN_TEXT_PUTS(ctx, &name, GRN_COLUMN_NAME_ID);
        break;
      case GRN_ACCESSOR_GET_KEY:
        if (!a->next) {
          ADD_DELMITER();
          GRN_TEXT_PUTS(ctx, &name, GRN_COLUMN_NAME_KEY);
        }
        break;
      case GRN_ACCESSOR_GET_VALUE:
        if (!a->next) {
          ADD_DELMITER();
          GRN_TEXT_PUTS(ctx, &name, GRN_COLUMN_NAME_VALUE);
        }
        break;
      case GRN_ACCESSOR_GET_SCORE:
        ADD_DELMITER();
        GRN_TEXT_PUTS(ctx, &name, GRN_COLUMN_NAME_SCORE);
        break;
      case GRN_ACCESSOR_GET_NSUBRECS:
        ADD_DELMITER();
        GRN_TEXT_PUTS(ctx, &name, GRN_COLUMN_NAME_NSUBRECS);
        break;
      case GRN_ACCESSOR_GET_MAX:
        ADD_DELMITER();
        GRN_TEXT_PUTS(ctx, &name, GRN_COLUMN_NAME_MAX);
        break;
      case GRN_ACCESSOR_GET_MIN:
        ADD_DELMITER();
        GRN_TEXT_PUTS(ctx, &name, GRN_COLUMN_NAME_MIN);
        break;
      case GRN_ACCESSOR_GET_SUM:
        ADD_DELMITER();
        GRN_TEXT_PUTS(ctx, &name, GRN_COLUMN_NAME_SUM);
        break;
      case GRN_ACCESSOR_GET_AVG:
        ADD_DELMITER();
        GRN_TEXT_PUTS(ctx, &name, GRN_COLUMN_NAME_AVG);
        break;
      case GRN_ACCESSOR_GET_MEAN:
        ADD_DELMITER();
        GRN_TEXT_PUTS(ctx, &name, GRN_COLUMN_NAME_MEAN);
        break;
      case GRN_ACCESSOR_GET_COLUMN_VALUE:
        ADD_DELMITER();
        {
          char column_name[GRN_TABLE_MAX_KEY_SIZE];
          int column_name_size;
          column_name_size =
            grn_column_name(ctx, a->obj, column_name, GRN_TABLE_MAX_KEY_SIZE);
          GRN_TEXT_PUT(ctx, &name, column_name, column_name_size);
        }
        break;
      case GRN_ACCESSOR_GET_DB_OBJ:
      case GRN_ACCESSOR_LOOKUP:
      case GRN_ACCESSOR_FUNCALL:
        break;
      }
    }
#undef ADD_DELIMITER

    len = GRN_TEXT_LEN(&name);
    if (len > 0 && len <= buf_size) {
      grn_memcpy(namebuf, GRN_TEXT_VALUE(&name), len);
    }

    GRN_OBJ_FIN(ctx, &name);
  }
  GRN_API_RETURN(len);
}

grn_rc
grn_column_name_(grn_ctx *ctx, grn_obj *obj, grn_obj *buf)
{
  if (GRN_DB_OBJP(obj)) {
    uint32_t len = 0;
    const char *p = NULL;
    grn_id id = DB_OBJ(obj)->id;
    if (id & GRN_OBJ_TMP_OBJECT) {
      if (id & GRN_OBJ_TMP_COLUMN) {
        grn_id real_id = id & ~(GRN_OBJ_TMP_OBJECT | GRN_OBJ_TMP_COLUMN);
        grn_ctx *target_ctx = ctx;
        while (target_ctx->impl->parent) {
          target_ctx = target_ctx->impl->parent;
        }
        p = _grn_pat_key(target_ctx,
                         target_ctx->impl->temporary_columns,
                         real_id,
                         &len);
      }
    } else if (id && id < GRN_ID_MAX) {
      grn_db *s = (grn_db *)DB_OBJ(obj)->db;
      p = _grn_table_key(ctx, s->keys, id, &len);
    }
    if (len) {
      int cl;
      const char *p0 = p, *pe = p + len;
      for (; p < pe && (cl = grn_charlen(ctx, p, pe)); p += cl) {
        if (*p == GRN_DB_DELIMITER && cl == 1) {
          p0 = p + cl;
        }
      }
      GRN_TEXT_PUT(ctx, buf, p0, pe - p0);
    }
  } else if (obj->header.type == GRN_ACCESSOR) {
    grn_accessor *a;
    for (a = (grn_accessor *)obj; a; a = a->next) {
      switch (a->action) {
      case GRN_ACCESSOR_GET_ID:
        GRN_TEXT_PUT(ctx, buf, GRN_COLUMN_NAME_ID, GRN_COLUMN_NAME_ID_LEN);
        break;
      case GRN_ACCESSOR_GET_KEY:
        if (!a->next) {
          GRN_TEXT_PUT(ctx, buf, GRN_COLUMN_NAME_KEY, GRN_COLUMN_NAME_KEY_LEN);
        }
        break;
      case GRN_ACCESSOR_GET_VALUE:
        if (!a->next) {
          GRN_TEXT_PUT(ctx,
                       buf,
                       GRN_COLUMN_NAME_VALUE,
                       GRN_COLUMN_NAME_VALUE_LEN);
        }
        break;
      case GRN_ACCESSOR_GET_SCORE:
        GRN_TEXT_PUT(ctx,
                     buf,
                     GRN_COLUMN_NAME_SCORE,
                     GRN_COLUMN_NAME_SCORE_LEN);
        break;
      case GRN_ACCESSOR_GET_NSUBRECS:
        GRN_TEXT_PUT(ctx,
                     buf,
                     GRN_COLUMN_NAME_NSUBRECS,
                     GRN_COLUMN_NAME_NSUBRECS_LEN);
        break;
      case GRN_ACCESSOR_GET_MAX:
        GRN_TEXT_PUT(ctx, buf, GRN_COLUMN_NAME_MAX, GRN_COLUMN_NAME_MAX_LEN);
        break;
      case GRN_ACCESSOR_GET_MIN:
        GRN_TEXT_PUT(ctx, buf, GRN_COLUMN_NAME_MIN, GRN_COLUMN_NAME_MIN_LEN);
        break;
      case GRN_ACCESSOR_GET_SUM:
        GRN_TEXT_PUT(ctx, buf, GRN_COLUMN_NAME_SUM, GRN_COLUMN_NAME_SUM_LEN);
        break;
      case GRN_ACCESSOR_GET_AVG:
        GRN_TEXT_PUT(ctx, buf, GRN_COLUMN_NAME_AVG, GRN_COLUMN_NAME_AVG_LEN);
        break;
      case GRN_ACCESSOR_GET_MEAN:
        GRN_TEXT_PUT(ctx, buf, GRN_COLUMN_NAME_MEAN, GRN_COLUMN_NAME_MEAN_LEN);
        break;
      case GRN_ACCESSOR_GET_COLUMN_VALUE:
        grn_column_name_(ctx, a->obj, buf);
        if (a->next) {
          GRN_TEXT_PUTC(ctx, buf, '.');
        }
        break;
      case GRN_ACCESSOR_GET_DB_OBJ:
      case GRN_ACCESSOR_LOOKUP:
      case GRN_ACCESSOR_FUNCALL:
        break;
      }
    }
  }
  return ctx->rc;
}

int
grn_obj_expire(grn_ctx *ctx, grn_obj *obj, int threshold)
{
  GRN_API_ENTER;
  GRN_API_RETURN(0);
}

int
grn_obj_check(grn_ctx *ctx, grn_obj *obj)
{
  GRN_API_ENTER;
  GRN_API_RETURN(0);
}

grn_rc
grn_obj_lock(grn_ctx *ctx, grn_obj *obj, grn_id id, int timeout)
{
  grn_rc rc = GRN_SUCCESS;
  GRN_API_ENTER;
  rc = grn_io_lock(ctx, grn_obj_get_io(ctx, obj), timeout);
  if (rc == GRN_SUCCESS && obj && obj->header.type == GRN_COLUMN_INDEX) {
    rc = grn_io_lock(ctx, ((grn_ii *)obj)->chunk, timeout);
  }
  GRN_API_RETURN(rc);
}

grn_rc
grn_obj_unlock(grn_ctx *ctx, grn_obj *obj, grn_id id)
{
  GRN_API_ENTER;
  if (obj && obj->header.type == GRN_COLUMN_INDEX) {
    grn_io_unlock(ctx, ((grn_ii *)obj)->chunk);
  }
  grn_io_unlock(ctx, grn_obj_get_io(ctx, obj));
  GRN_API_RETURN(GRN_SUCCESS);
}

grn_user_data *
grn_obj_user_data(grn_ctx *ctx, grn_obj *obj)
{
  if (!GRN_DB_OBJP(obj)) {
    return NULL;
  }
  return &DB_OBJ(obj)->user_data;
}

grn_rc
grn_obj_set_finalizer(grn_ctx *ctx, grn_obj *obj, grn_proc_func *func)
{
  if (!GRN_DB_OBJP(obj)) {
    return GRN_INVALID_ARGUMENT;
  }
  DB_OBJ(obj)->finalizer = func;
  return GRN_SUCCESS;
}

grn_rc
grn_obj_clear_lock(grn_ctx *ctx, grn_obj *obj)
{
  GRN_API_ENTER;
  switch (obj->header.type) {
  case GRN_DB:
    {
      grn_table_cursor *cur;
      if ((cur = grn_table_cursor_open(ctx, obj, NULL, 0, NULL, 0, 0, -1, 0))) {
        grn_id id;
        while ((id = grn_table_cursor_next_inline(ctx, cur)) != GRN_ID_NIL) {
          grn_obj *tbl = grn_ctx_at(ctx, id);
          if (tbl) {
            switch (tbl->header.type) {
            case GRN_TABLE_HASH_KEY:
            case GRN_TABLE_PAT_KEY:
            case GRN_TABLE_DAT_KEY:
            case GRN_TABLE_NO_KEY:
              grn_obj_clear_lock(ctx, tbl);
              break;
            }
          } else {
            if (ctx->rc != GRN_SUCCESS) {
              ERRCLR(ctx);
            }
          }
        }
        grn_table_cursor_close(ctx, cur);
      }
    }
    grn_io_clear_lock(grn_obj_get_io(ctx, obj));
    {
      grn_db *db = (grn_db *)obj;
      if (db->specs) {
        grn_obj_clear_lock(ctx, (grn_obj *)(db->specs));
      }
      grn_obj_clear_lock(ctx, (grn_obj *)(db->config));
      grn_options_clear_lock(ctx, db->options);
    }
    break;
  case GRN_TABLE_NO_KEY:
  case GRN_TABLE_HASH_KEY:
  case GRN_TABLE_PAT_KEY:
  case GRN_TABLE_DAT_KEY:
    {
      grn_hash *cols;
      if ((cols = grn_hash_create(ctx,
                                  NULL,
                                  sizeof(grn_id),
                                  0,
                                  GRN_OBJ_TABLE_HASH_KEY | GRN_HASH_TINY))) {
        if (grn_table_columns(ctx, obj, "", 0, (grn_obj *)cols)) {
          grn_id *key;
          GRN_HASH_EACH(ctx, cols, id, &key, NULL, NULL, {
            grn_obj *col = grn_ctx_at(ctx, *key);
            if (col) {
              grn_obj_clear_lock(ctx, col);
            }
          });
        }
        grn_hash_close(ctx, cols);
      }
      grn_io_clear_lock(grn_obj_get_io(ctx, obj));
    }
    break;
  case GRN_COLUMN_FIX_SIZE:
  case GRN_COLUMN_VAR_SIZE:
    grn_io_clear_lock(grn_obj_get_io(ctx, obj));
    break;
  case GRN_COLUMN_INDEX:
    grn_io_clear_lock(grn_obj_get_io(ctx, obj));
    if (obj) {
      grn_io_clear_lock(((grn_ii *)obj)->chunk);
    }
    break;
  }
  GRN_API_RETURN(GRN_SUCCESS);
}

unsigned int
grn_obj_is_locked(grn_ctx *ctx, grn_obj *obj)
{
  unsigned int res = 0;
  GRN_API_ENTER;
  res = grn_io_is_locked(grn_obj_get_io(ctx, obj));
  if (obj) {
    switch (obj->header.type) {
    case GRN_DB:
      {
        grn_db *db = (grn_db *)obj;
        if (db->specs) {
          res += grn_obj_is_locked(ctx, (grn_obj *)(db->specs));
        }
        res += grn_obj_is_locked(ctx, (grn_obj *)db->config);
        if (grn_options_is_locked(ctx, db->options)) {
          res++;
        }
      }
      break;
    case GRN_COLUMN_INDEX:
      res += grn_io_is_locked(((grn_ii *)obj)->chunk);
      break;
    }
  }
  GRN_API_RETURN(res);
}

static grn_rc
grn_obj_flush_raw(grn_ctx *ctx, grn_obj *obj)
{
  grn_rc rc = GRN_OPERATION_NOT_SUPPORTED;
  grn_io *io = grn_obj_get_io(ctx, obj);
  if (io) {
    rc = grn_io_flush(ctx, io);
  }
  return rc;
}

static grn_rc
grn_obj_flush_without_lock(grn_ctx *ctx, grn_obj *obj, const char *tag)
{
  grn_rc rc = GRN_SUCCESS;

  char name[GRN_TABLE_MAX_KEY_SIZE];
  int name_size = 0;
  bool flushed = false;
  switch (obj->header.type) {
  case GRN_DB:
    {
      grn_db *db = (grn_db *)obj;
      rc = grn_obj_flush_without_lock(ctx, db->keys, tag);
      if (rc == GRN_SUCCESS && db->specs) {
        rc = grn_obj_flush_without_lock(ctx, (grn_obj *)(db->specs), tag);
      }
      if (rc == GRN_SUCCESS) {
        rc = grn_obj_flush_without_lock(ctx, (grn_obj *)(db->config), tag);
      }
      if (rc == GRN_SUCCESS) {
        rc = grn_options_flush(ctx, db->options);
      }
    }
    grn_strcpy(name, GRN_TABLE_MAX_KEY_SIZE, "(DB)");
    name_size = strlen(name);
    flushed = true;
    break;
  case GRN_TABLE_DAT_KEY:
    rc = grn_dat_flush(ctx, (grn_dat *)obj);
    flushed = true;
    break;
  case GRN_COLUMN_INDEX:
    rc = grn_ii_flush(ctx, (grn_ii *)obj);
    flushed = true;
    break;
  default:
    {
      grn_rc rc_raw = grn_obj_flush_raw(ctx, obj);
      if (rc_raw != GRN_OPERATION_NOT_SUPPORTED) {
        if (rc_raw != GRN_SUCCESS) {
          rc = rc_raw;
        }
        flushed = true;
      }
    }
    break;
  }

  if (flushed && rc == GRN_SUCCESS) {
    grn_wal_clear(ctx, obj, false, tag);
  }

  if (flushed && name_size == 0) {
    name_size = grn_obj_name(ctx, obj, name, GRN_TABLE_MAX_KEY_SIZE);
    if (name_size == 0) {
      grn_strcpy(name, GRN_TABLE_MAX_KEY_SIZE, "(anonymous:");
      grn_strcat(name,
                 GRN_TABLE_MAX_KEY_SIZE,
                 grn_obj_type_to_string(obj->header.type));
      grn_strcat(name, GRN_TABLE_MAX_KEY_SIZE, ")");
      name_size = strlen(name);
    }
  }

  if (name_size > 0) {
    GRN_QUERY_LOG(ctx, GRN_QUERY_LOG_SIZE, ":", "flush[%.*s]", name_size, name);
  }

  if (rc == GRN_SUCCESS && GRN_DB_OBJP(obj) && DB_OBJ(obj)->id != GRN_ID_NIL &&
      !IS_TEMP(obj)) {
    rc = grn_db_clean(ctx, DB_OBJ(obj)->db);
  }

  return rc;
}

static grn_rc
grn_obj_flush_lock(grn_ctx *ctx, grn_obj *obj, const char *tag)
{
  if (!grn_obj_get_io(ctx, obj)) {
    return GRN_SUCCESS;
  }

  grn_rc rc = grn_obj_lock(ctx, obj, GRN_ID_NIL, grn_lock_timeout);
  if (rc != GRN_SUCCESS) {
    char errbuf[GRN_CTX_MSGSIZE];
    grn_strcpy(errbuf, GRN_CTX_MSGSIZE, ctx->errbuf);
    grn_obj inspected;
    GRN_TEXT_INIT(&inspected, 0);
    grn_inspect(ctx, &inspected, obj);
    ERR(rc,
        "%s failed to lock%s%s: <%.*s>",
        tag,
        errbuf[0] == '\0' ? "" : ": ",
        errbuf,
        (int)GRN_TEXT_LEN(&inspected),
        GRN_TEXT_VALUE(&inspected));
    GRN_OBJ_FIN(ctx, &inspected);
  }
  return rc;
}

static grn_rc
grn_obj_flush_unlock(grn_ctx *ctx, grn_obj *obj, const char *tag)
{
  if (!grn_obj_get_io(ctx, obj)) {
    return GRN_SUCCESS;
  }

  grn_rc rc = grn_obj_unlock(ctx, obj, GRN_ID_NIL);
  if (rc != GRN_SUCCESS) {
    char errbuf[GRN_CTX_MSGSIZE];
    grn_strcpy(errbuf, GRN_CTX_MSGSIZE, ctx->errbuf);
    grn_obj inspected;
    GRN_TEXT_INIT(&inspected, 0);
    grn_inspect(ctx, &inspected, obj);
    ERR(rc,
        "%s failed to unlock%s%s: <%.*s>",
        tag,
        errbuf[0] == '\0' ? "" : ": ",
        errbuf,
        (int)GRN_TEXT_LEN(&inspected),
        GRN_TEXT_VALUE(&inspected));
    GRN_OBJ_FIN(ctx, &inspected);
    return rc;
  }

  /* For flushing io->lock */
  return grn_obj_flush_raw(ctx, obj);
}

static grn_rc
grn_obj_flush_internal(grn_ctx *ctx, grn_obj *obj, const char *tag)
{
  bool need_lock = ((GRN_CTX_GET_WAL_ROLE(ctx) == GRN_WAL_ROLE_PRIMARY) &&
                    grn_wal_exist(ctx, obj));
  grn_rc rc = GRN_SUCCESS;
  if (need_lock) {
    rc = grn_obj_flush_lock(ctx, obj, tag);
    if (rc != GRN_SUCCESS) {
      return rc;
    }
  }
  rc = grn_obj_flush_without_lock(ctx, obj, tag);
  if (need_lock) {
    grn_rc rc_unlock = grn_obj_flush_unlock(ctx, obj, tag);
    if (rc == GRN_SUCCESS && rc_unlock != GRN_SUCCESS) {
      rc = rc_unlock;
    }
  }

  return rc;
}

grn_rc
grn_obj_flush(grn_ctx *ctx, grn_obj *obj)
{
  GRN_API_ENTER;
  grn_rc rc = grn_obj_flush_internal(ctx, obj, "[obj][flush]");
  GRN_API_RETURN(rc);
}

typedef struct {
  const char *tag;
  grn_obj *top_obj;
} grn_obj_flush_traverse_data;

static void
grn_obj_flush_traverse(grn_ctx *ctx, grn_obj *obj, void *user_data)
{
  grn_obj_flush_traverse_data *data = user_data;
  if (obj == data->top_obj) {
    grn_obj_flush_without_lock(ctx, obj, data->tag);
  } else {
    grn_obj_flush_internal(ctx, obj, data->tag);
  }
}

grn_rc
grn_obj_flush_recursive(grn_ctx *ctx, grn_obj *obj)
{
  GRN_API_ENTER;

  grn_obj_flush_traverse_data traverse_data;
  traverse_data.tag = "[obj][flush][recursive]";
  traverse_data.top_obj = obj;
  grn_obj_traverse_recursive_data data;
  data.tag = "[obj][flush]";
  data.traverse = grn_obj_flush_traverse;
  data.user_data = &traverse_data;

  grn_obj *db = grn_ctx_db(ctx);
  grn_rc rc = grn_obj_flush_lock(ctx, db, traverse_data.tag);
  if (rc != GRN_SUCCESS) {
    GRN_API_RETURN(rc);
  }
  if (obj != db) {
    rc = grn_obj_flush_lock(ctx, obj, traverse_data.tag);
    if (rc != GRN_SUCCESS) {
      grn_obj_flush_unlock(ctx, db, traverse_data.tag);
      GRN_API_RETURN(rc);
    }
  }
  grn_obj_traverse_recursive(ctx, &data, obj);
  if (obj != db) {
    grn_obj_flush_unlock(ctx, obj, traverse_data.tag);
  }
  grn_obj_flush_unlock(ctx, db, traverse_data.tag);

  GRN_API_RETURN(ctx->rc);
}

grn_rc
grn_obj_flush_recursive_dependent(grn_ctx *ctx, grn_obj *obj)
{
  GRN_API_ENTER;

  grn_obj_flush_traverse_data traverse_data;
  traverse_data.tag = "[obj][flush][recursive][dependent]";
  traverse_data.top_obj = obj;
  grn_obj_traverse_recursive_dependent_data data;
  data.tag = "[obj][flush]";
  data.traverse = grn_obj_flush_traverse;
  data.user_data = &traverse_data;
  data.for_reference = false;

  grn_obj *db = grn_ctx_db(ctx);
  grn_rc rc = grn_obj_flush_lock(ctx, db, traverse_data.tag);
  if (rc != GRN_SUCCESS) {
    GRN_API_RETURN(rc);
  }
  if (obj != db) {
    rc = grn_obj_flush_lock(ctx, obj, traverse_data.tag);
    if (rc != GRN_SUCCESS) {
      grn_obj_flush_unlock(ctx, db, traverse_data.tag);
      GRN_API_RETURN(rc);
    }
  }
  grn_obj_traverse_recursive_dependent(ctx, &data, obj);
  if (obj != db) {
    grn_obj_flush_unlock(ctx, obj, traverse_data.tag);
  }
  grn_obj_flush_unlock(ctx, db, traverse_data.tag);

  GRN_API_RETURN(ctx->rc);
}

grn_rc
grn_obj_flush_only_opened(grn_ctx *ctx, grn_obj *obj)
{
  GRN_API_ENTER;

  const char *tag = "[obj][flush][only-opened]";

  if (!grn_obj_is_db(ctx, obj)) {
    grn_obj inspected;
    GRN_TEXT_INIT(&inspected, 0);
    grn_inspect(ctx, &inspected, obj);
    ERR(GRN_INVALID_ARGUMENT,
        "%s DB is only support for now: <%.*s>",
        tag,
        (int)GRN_TEXT_LEN(&inspected),
        GRN_TEXT_VALUE(&inspected));
    GRN_OBJ_FIN(ctx, &inspected);
    GRN_API_RETURN(ctx->rc);
  }

  grn_rc rc = grn_obj_flush_lock(ctx, obj, tag);
  if (rc != GRN_SUCCESS) {
    GRN_API_RETURN(rc);
  }

  GRN_TABLE_EACH_BEGIN_FLAGS(ctx, obj, cursor, id, GRN_CURSOR_BY_ID)
  {
    if (id < GRN_N_RESERVED_TYPES) {
      continue;
    }

    if (!grn_ctx_is_opened(ctx, id)) {
      continue;
    }

    grn_obj *sub_obj = grn_ctx_at(ctx, id);
    rc = grn_obj_flush_internal(ctx, sub_obj, tag);
    grn_obj_unref(ctx, sub_obj);
    if (rc != GRN_SUCCESS) {
      break;
    }
  }
  GRN_TABLE_EACH_END(ctx, cursor);
  if (rc == GRN_SUCCESS) {
    rc = grn_obj_flush_without_lock(ctx, obj, tag);
  }

  grn_rc rc_unlock = grn_obj_flush_unlock(ctx, obj, tag);
  if (rc == GRN_SUCCESS && rc_unlock != GRN_SUCCESS) {
    rc = rc_unlock;
  }

  GRN_API_RETURN(rc);
}

grn_obj *
grn_obj_db(grn_ctx *ctx, grn_obj *obj)
{
  grn_obj *db = NULL;
  GRN_API_ENTER;
  if (GRN_DB_OBJP(obj)) {
    db = DB_OBJ(obj)->db;
  }
  GRN_API_RETURN(db);
}

grn_id
grn_obj_id(grn_ctx *ctx, grn_obj *obj)
{
  grn_id id = GRN_ID_NIL;
  GRN_API_ENTER;
  if (GRN_DB_OBJP(obj)) {
    id = DB_OBJ(obj)->id;
  }
  GRN_API_RETURN(id);
}

int
grn_obj_defrag(grn_ctx *ctx, grn_obj *obj, int threshold)
{
  int r = 0;
  GRN_API_ENTER;
  switch (obj->header.type) {
  case GRN_DB:
    {
      grn_table_cursor *cur;
      if ((cur = grn_table_cursor_open(ctx, obj, NULL, 0, NULL, 0, 0, -1, 0))) {
        grn_id id;
        while ((id = grn_table_cursor_next_inline(ctx, cur)) != GRN_ID_NIL) {
          grn_obj *target_object = grn_ctx_at(ctx, id);
          if (!target_object) {
            continue;
          }
          switch (target_object->header.type) {
          case GRN_TABLE_PAT_KEY:
            GRN_TABLE_LOCK_BEGIN(ctx, target_object)
            {
              r += grn_pat_defrag(ctx, (grn_pat *)target_object);
            }
            GRN_TABLE_LOCK_END(ctx);
            break;
          case GRN_COLUMN_VAR_SIZE:
            r += grn_ja_defrag(ctx, (grn_ja *)target_object, threshold);
            break;
          }
        }
        grn_table_cursor_close(ctx, cur);
      }
    }
    break;
  case GRN_TABLE_PAT_KEY:
    GRN_TABLE_LOCK_BEGIN(ctx, obj) { r = grn_pat_defrag(ctx, (grn_pat *)obj); }
    GRN_TABLE_LOCK_END(ctx);
    break;
  case GRN_TABLE_HASH_KEY:
  case GRN_TABLE_DAT_KEY:
  case GRN_TABLE_NO_KEY:
    {
      grn_hash *cols;
      if ((cols = grn_hash_create(ctx,
                                  NULL,
                                  sizeof(grn_id),
                                  0,
                                  GRN_OBJ_TABLE_HASH_KEY | GRN_HASH_TINY))) {
        if (grn_table_columns(ctx, obj, "", 0, (grn_obj *)cols)) {
          grn_id *key;
          GRN_HASH_EACH(ctx, cols, id, &key, NULL, NULL, {
            grn_obj *col = grn_ctx_at(ctx, *key);
            if (col) {
              r += grn_obj_defrag(ctx, col, threshold);
              grn_obj_unlink(ctx, col);
            }
          });
        }
        grn_hash_close(ctx, cols);
      }
    }
    break;
  case GRN_COLUMN_VAR_SIZE:
    r = grn_ja_defrag(ctx, (grn_ja *)obj, threshold);
    break;
  }
  GRN_API_RETURN(r);
}

static grn_obj *
deftype(grn_ctx *ctx, const char *name, grn_obj_flags flags, unsigned int size)
{
  grn_obj *o = grn_ctx_get(ctx, name, strlen(name));
  if (!o) {
    o = grn_type_create(ctx, name, strlen(name), flags, size);
  }
  return o;
}

grn_rc
grn_db_init_builtin_types(grn_ctx *ctx)
{
  grn_id id;
  grn_obj *obj, *db = ctx->impl->db;
  char buf[] = "Sys00";
  grn_obj_register(ctx, db, buf, 5);
  obj = deftype(ctx, "Object", GRN_OBJ_KEY_UINT, sizeof(uint64_t));
  if (!obj || DB_OBJ(obj)->id != GRN_DB_OBJECT) {
    return GRN_FILE_CORRUPT;
  }
  obj = deftype(ctx, "Bool", GRN_OBJ_KEY_UINT, sizeof(uint8_t));
  if (!obj || DB_OBJ(obj)->id != GRN_DB_BOOL) {
    return GRN_FILE_CORRUPT;
  }
  obj = deftype(ctx, "Int8", GRN_OBJ_KEY_INT, sizeof(int8_t));
  if (!obj || DB_OBJ(obj)->id != GRN_DB_INT8) {
    return GRN_FILE_CORRUPT;
  }
  obj = deftype(ctx, "UInt8", GRN_OBJ_KEY_UINT, sizeof(uint8_t));
  if (!obj || DB_OBJ(obj)->id != GRN_DB_UINT8) {
    return GRN_FILE_CORRUPT;
  }
  obj = deftype(ctx, "Int16", GRN_OBJ_KEY_INT, sizeof(int16_t));
  if (!obj || DB_OBJ(obj)->id != GRN_DB_INT16) {
    return GRN_FILE_CORRUPT;
  }
  obj = deftype(ctx, "UInt16", GRN_OBJ_KEY_UINT, sizeof(uint16_t));
  if (!obj || DB_OBJ(obj)->id != GRN_DB_UINT16) {
    return GRN_FILE_CORRUPT;
  }
  obj = deftype(ctx, "Int32", GRN_OBJ_KEY_INT, sizeof(int32_t));
  if (!obj || DB_OBJ(obj)->id != GRN_DB_INT32) {
    return GRN_FILE_CORRUPT;
  }
  obj = deftype(ctx, "UInt32", GRN_OBJ_KEY_UINT, sizeof(uint32_t));
  if (!obj || DB_OBJ(obj)->id != GRN_DB_UINT32) {
    return GRN_FILE_CORRUPT;
  }
  obj = deftype(ctx, "Int64", GRN_OBJ_KEY_INT, sizeof(int64_t));
  if (!obj || DB_OBJ(obj)->id != GRN_DB_INT64) {
    return GRN_FILE_CORRUPT;
  }
  obj = deftype(ctx, "UInt64", GRN_OBJ_KEY_UINT, sizeof(uint64_t));
  if (!obj || DB_OBJ(obj)->id != GRN_DB_UINT64) {
    return GRN_FILE_CORRUPT;
  }
  obj = deftype(ctx, "Float", GRN_OBJ_KEY_FLOAT, sizeof(double));
  if (!obj || DB_OBJ(obj)->id != GRN_DB_FLOAT) {
    return GRN_FILE_CORRUPT;
  }
  obj = deftype(ctx, "Time", GRN_OBJ_KEY_INT, sizeof(int64_t));
  if (!obj || DB_OBJ(obj)->id != GRN_DB_TIME) {
    return GRN_FILE_CORRUPT;
  }
  obj =
    deftype(ctx, "ShortText", GRN_OBJ_KEY_VAR_SIZE, GRN_TYPE_SHORT_TEXT_SIZE);
  if (!obj || DB_OBJ(obj)->id != GRN_DB_SHORT_TEXT) {
    return GRN_FILE_CORRUPT;
  }
  obj = deftype(ctx, "Text", GRN_OBJ_KEY_VAR_SIZE, GRN_TYPE_TEXT_SIZE);
  if (!obj || DB_OBJ(obj)->id != GRN_DB_TEXT) {
    return GRN_FILE_CORRUPT;
  }
  obj = deftype(ctx, "LongText", GRN_OBJ_KEY_VAR_SIZE, GRN_TYPE_LONG_TEXT_SIZE);
  if (!obj || DB_OBJ(obj)->id != GRN_DB_LONG_TEXT) {
    return GRN_FILE_CORRUPT;
  }
  obj =
    deftype(ctx, "TokyoGeoPoint", GRN_OBJ_KEY_GEO_POINT, sizeof(grn_geo_point));
  if (!obj || DB_OBJ(obj)->id != GRN_DB_TOKYO_GEO_POINT) {
    return GRN_FILE_CORRUPT;
  }
  obj =
    deftype(ctx, "WGS84GeoPoint", GRN_OBJ_KEY_GEO_POINT, sizeof(grn_geo_point));
  if (!obj || DB_OBJ(obj)->id != GRN_DB_WGS84_GEO_POINT) {
    return GRN_FILE_CORRUPT;
  }
  obj = deftype(ctx,
                GRN_TYPE_FLOAT32_NAME,
                GRN_TYPE_FLOAT32_FLAGS,
                GRN_TYPE_FLOAT32_SIZE);
  if (!obj || DB_OBJ(obj)->id != GRN_DB_FLOAT32) {
    return GRN_FILE_CORRUPT;
  }
  obj = deftype(ctx,
                GRN_TYPE_BFLOAT16_NAME,
                GRN_TYPE_BFLOAT16_FLAGS,
                GRN_TYPE_BFLOAT16_SIZE);
  if (!obj || DB_OBJ(obj)->id != GRN_DB_BFLOAT16) {
    return GRN_FILE_CORRUPT;
  }
  for (id = grn_db_curr_id(ctx, db) + 1; id < GRN_DB_MECAB; id++) {
    grn_itoh(id, buf + 3, 2);
    grn_obj_register(ctx, db, buf, 5);
  }
#ifdef GRN_WITH_MECAB
  if (grn_db_init_mecab_tokenizer(ctx)) {
    ERRCLR(ctx);
#endif
    grn_obj_register(ctx, db, "TokenMecab", 10);
#ifdef GRN_WITH_MECAB
  }
#endif
  grn_db_init_builtin_tokenizers(ctx);
  grn_db_init_builtin_normalizers(ctx);
  grn_db_init_builtin_scorers(ctx);
  for (id = grn_db_curr_id(ctx, db) + 1; id < 128; id++) {
    grn_itoh(id, buf + 3, 2);
    grn_obj_register(ctx, db, buf, 5);
  }
  grn_db_init_builtin_commands(ctx);
  grn_db_init_builtin_window_functions(ctx);
  grn_db_init_builtin_token_filters(ctx);
  grn_db_init_builtin_aggregators(ctx);
  for (id = grn_db_curr_id(ctx, db) + 1; id < GRN_N_RESERVED_TYPES; id++) {
    grn_itoh(id, buf + 3, 2);
    grn_obj_register(ctx, db, buf, 5);
  }
  return ctx->rc;
}

#define MULTI_COLUMN_INDEXP(i) (DB_OBJ(i)->source_size > sizeof(grn_id))

static void
report_hook_has_dangling_reference_error(grn_ctx *ctx,
                                         grn_obj *target,
                                         grn_id reference_id,
                                         const char *context_tag)
{
  char target_name[GRN_TABLE_MAX_KEY_SIZE];
  int target_name_length;
  char reference_name[GRN_TABLE_MAX_KEY_SIZE];
  int reference_name_length;

  target_name_length =
    grn_obj_name(ctx, target, target_name, GRN_TABLE_MAX_KEY_SIZE);
  reference_name_length = grn_table_get_key(ctx,
                                            ctx->impl->db,
                                            reference_id,
                                            reference_name,
                                            GRN_TABLE_MAX_KEY_SIZE);
  ERR(GRN_OBJECT_CORRUPT,
      "%s hook has a dangling reference: <%.*s> -> <%.*s>(%u)",
      context_tag,
      target_name_length,
      target_name,
      reference_name_length,
      reference_name,
      reference_id);
}

static grn_bool
is_full_text_searchable_index(grn_ctx *ctx, grn_obj *index_column)
{
  grn_obj *tokenizer;

  tokenizer = grn_index_column_get_tokenizer(ctx, index_column);
  return tokenizer != NULL;
}

typedef struct {
  grn_operator op;
  grn_index_datum *index_data;
  uint32_t n_index_data;
  grn_obj **index_buffer;
  uint32_t n_index_buffers;
  int *section_buffer;
  grn_obj referred_objects;
  uint32_t n_found_indexes;
} grn_find_index_data;

static void
grn_find_index_data_init(grn_ctx *ctx,
                         grn_find_index_data *data,
                         grn_operator op,
                         grn_index_datum *index_data,
                         unsigned int n_index_data,
                         grn_obj **index_buffer,
                         int n_index_buffers,
                         int *section_buffer)
{
  data->op = op;
  data->index_data = index_data;
  data->n_index_data = n_index_data;
  data->index_buffer = index_buffer;
  data->n_index_buffers = n_index_buffers;
  data->section_buffer = section_buffer;
  if (data->section_buffer) {
    *(data->section_buffer) = 0;
  }
  GRN_PTR_INIT(&(data->referred_objects), GRN_OBJ_VECTOR, GRN_ID_NIL);
  data->n_found_indexes = 0;
}

static void
grn_find_index_data_fin(grn_ctx *ctx, grn_find_index_data *data)
{
  if (grn_enable_reference_count) {
    size_t i;
    size_t n = GRN_PTR_VECTOR_SIZE(&(data->referred_objects));
    for (i = 0; i < n; i++) {
      grn_obj *obj = GRN_PTR_VALUE_AT(&(data->referred_objects), i);
      grn_obj_unlink(ctx, obj);
    }
  }
  GRN_OBJ_FIN(ctx, &(data->referred_objects));
}

static void
grn_find_index_data_referred(grn_ctx *ctx,
                             grn_find_index_data *data,
                             grn_obj *index)
{
  if (grn_enable_reference_count) {
    GRN_PTR_PUT(ctx, &(data->referred_objects), index);
  }
}

static void
grn_find_index_data_refer(grn_ctx *ctx, grn_find_index_data *data, grn_obj *obj)
{
  if (!grn_enable_reference_count) {
    return;
  }

  grn_obj_refer(ctx, obj);
  grn_find_index_data_referred(ctx, data, obj);
}

static void
grn_find_index_data_found(grn_ctx *ctx,
                          grn_find_index_data *data,
                          grn_obj *index,
                          int section)
{
  if (grn_enable_reference_count) {
    size_t n_referred_objects = GRN_PTR_VECTOR_SIZE(&(data->referred_objects));
    if (n_referred_objects > 0) {
      grn_obj *last_referred_object =
        GRN_PTR_VALUE_AT(&(data->referred_objects), n_referred_objects - 1);
      if (last_referred_object == index) {
        grn_obj *found_object;
        GRN_PTR_POP(&(data->referred_objects), found_object);
      }
    }
  }

  if (data->section_buffer) {
    *(data->section_buffer) = section;
  }
  if (data->n_found_indexes < data->n_index_buffers) {
    data->index_buffer[data->n_found_indexes] = index;
  }
  if (data->n_found_indexes < data->n_index_data) {
    data->index_data[data->n_found_indexes].index = index;
    data->index_data[data->n_found_indexes].section = section;
  }
  data->n_found_indexes++;
}

static void
grn_column_find_index_data_column_equal(grn_ctx *ctx,
                                        grn_obj *obj,
                                        grn_find_index_data *data)
{
  grn_hook *hooks;

  for (hooks = DB_OBJ(obj)->hooks[GRN_HOOK_SET]; hooks; hooks = hooks->next) {
    grn_obj_default_set_value_hook_data *hook_data =
      (void *)GRN_NEXT_ADDR(hooks);
    grn_obj *target = grn_ctx_at(ctx, hook_data->target);

    if (!target) {
      report_hook_has_dangling_reference_error(ctx,
                                               obj,
                                               hook_data->target,
                                               "[column][index]"
                                               "[column][equal]");
      continue;
    }

    grn_find_index_data_referred(ctx, data, target);
    if (target->header.type != GRN_COLUMN_INDEX) {
      continue;
    }
    if (!grn_index_column_is_usable(ctx, target, data->op)) {
      continue;
    }
    if (obj->header.type != GRN_COLUMN_FIX_SIZE) {
      if (is_full_text_searchable_index(ctx, target)) {
        continue;
      }
    }

    int section = (MULTI_COLUMN_INDEXP(target)) ? hook_data->section : 0;
    grn_find_index_data_found(ctx, data, target, section);
  }
}

static void
grn_column_find_index_data_column_match(grn_ctx *ctx,
                                        grn_obj *obj,
                                        grn_find_index_data *data)
{
  grn_hook_entry hook_entry;
  grn_hook *hooks;
  bool prefer_full_text_search_index = false;

  switch (obj->header.type) {
  case GRN_TABLE_HASH_KEY:
  case GRN_TABLE_PAT_KEY:
  case GRN_TABLE_DAT_KEY:
  case GRN_TABLE_NO_KEY:
    hook_entry = GRN_HOOK_INSERT;
    break;
  default:
    hook_entry = GRN_HOOK_SET;
    break;
  }

  switch (data->op) {
  case GRN_OP_PREFIX:
    switch (obj->header.type) {
    case GRN_TABLE_PAT_KEY:
    case GRN_TABLE_DAT_KEY:
      grn_find_index_data_refer(ctx, data, obj);
      grn_find_index_data_found(ctx, data, obj, 0);
      break;
    default:
      break;
    }
    break;
  case GRN_OP_SUFFIX:
    if (obj->header.type == GRN_TABLE_PAT_KEY &&
        obj->header.flags & GRN_OBJ_KEY_WITH_SIS) {
      grn_find_index_data_refer(ctx, data, obj);
      grn_find_index_data_found(ctx, data, obj, 0);
    }
    break;
  case GRN_OP_MATCH:
    prefer_full_text_search_index = !grn_column_is_vector(ctx, obj);
    break;
  case GRN_OP_NEAR:
  case GRN_OP_NEAR_NO_OFFSET:
  case GRN_OP_NEAR_PHRASE:
  case GRN_OP_ORDERED_NEAR_PHRASE:
  case GRN_OP_NEAR_PHRASE_PRODUCT:
  case GRN_OP_ORDERED_NEAR_PHRASE_PRODUCT:
  case GRN_OP_SIMILAR:
    prefer_full_text_search_index = true;
    break;
  default:
    break;
  }

  if (prefer_full_text_search_index) {
    for (hooks = DB_OBJ(obj)->hooks[hook_entry]; hooks; hooks = hooks->next) {
      grn_obj_default_set_value_hook_data *hook_data =
        (void *)GRN_NEXT_ADDR(hooks);
      grn_obj *target = grn_ctx_at(ctx, hook_data->target);
      if (!target) {
        report_hook_has_dangling_reference_error(ctx,
                                                 obj,
                                                 hook_data->target,
                                                 "[column][index]"
                                                 "[column][match]"
                                                 "[prefer-full-text-search]");
        continue;
      }

      grn_find_index_data_referred(ctx, data, target);
      if (target->header.type != GRN_COLUMN_INDEX) {
        continue;
      }
      if (!grn_index_column_is_usable(ctx, target, data->op)) {
        continue;
      }
      if (!is_full_text_searchable_index(ctx, target)) {
        continue;
      }

      int section = (MULTI_COLUMN_INDEXP(target)) ? hook_data->section : 0;
      grn_find_index_data_found(ctx, data, target, section);
    }
  }

  for (hooks = DB_OBJ(obj)->hooks[hook_entry]; hooks; hooks = hooks->next) {
    grn_obj_default_set_value_hook_data *hook_data =
      (void *)GRN_NEXT_ADDR(hooks);
    grn_obj *target = grn_ctx_at(ctx, hook_data->target);

    if (!target) {
      report_hook_has_dangling_reference_error(ctx,
                                               obj,
                                               hook_data->target,
                                               "[column][index]"
                                               "[column][match]");
      continue;
    }

    grn_find_index_data_referred(ctx, data, target);
    if (target->header.type != GRN_COLUMN_INDEX) {
      continue;
    }
    if (!grn_index_column_is_usable(ctx, target, data->op)) {
      continue;
    }
    if (prefer_full_text_search_index) {
      if (is_full_text_searchable_index(ctx, target)) {
        continue;
      }
    }

    int section = (MULTI_COLUMN_INDEXP(target)) ? hook_data->section : 0;
    grn_find_index_data_found(ctx, data, target, section);
  }
}

static void
grn_column_find_index_data_column_range(grn_ctx *ctx,
                                        grn_obj *obj,
                                        grn_find_index_data *data)
{
  grn_hook_entry hook_entry;
  grn_hook *hooks;

  switch (obj->header.type) {
  case GRN_TABLE_HASH_KEY:
  case GRN_TABLE_PAT_KEY:
  case GRN_TABLE_DAT_KEY:
  case GRN_TABLE_NO_KEY:
    hook_entry = GRN_HOOK_INSERT;
    break;
  default:
    hook_entry = GRN_HOOK_SET;
    break;
  }

  for (hooks = DB_OBJ(obj)->hooks[hook_entry]; hooks; hooks = hooks->next) {
    grn_obj_default_set_value_hook_data *hook_data =
      (void *)GRN_NEXT_ADDR(hooks);
    grn_obj *target = grn_ctx_at(ctx, hook_data->target);

    if (!target) {
      report_hook_has_dangling_reference_error(ctx,
                                               obj,
                                               hook_data->target,
                                               "[column][index]"
                                               "[column][range]");
      continue;
    }

    grn_find_index_data_referred(ctx, data, target);
    if (target->header.type != GRN_COLUMN_INDEX) {
      continue;
    }
    if (!grn_index_column_is_usable(ctx, target, data->op)) {
      continue;
    }

    int section = (MULTI_COLUMN_INDEXP(target)) ? hook_data->section : 0;
    grn_obj *lexicon = grn_ctx_at(ctx, target->header.domain);
    grn_obj *tokenizer;
    if (!lexicon) {
      report_hook_has_dangling_reference_error(ctx,
                                               target,
                                               target->header.domain,
                                               "[column][index]"
                                               "[column][range][lexicon]");
      continue;
    }
    /* FIXME: GRN_TABLE_DAT_KEY should be supported */
    if (lexicon->header.type != GRN_TABLE_PAT_KEY) {
      grn_obj_unref(ctx, lexicon);
      continue;
    }
    grn_table_get_info(ctx, lexicon, NULL, NULL, &tokenizer, NULL, NULL);
    grn_obj_unref(ctx, lexicon);
    if (tokenizer) {
      continue;
    }
    grn_find_index_data_found(ctx, data, target, section);
  }
}

static int
find_section(grn_ctx *ctx, grn_obj *index_column, grn_obj *indexed_column)
{
  int section = 0;
  grn_id indexed_column_id;
  grn_id *source_ids;
  int i, n_source_ids;

  indexed_column_id = DB_OBJ(indexed_column)->id;

  source_ids = DB_OBJ(index_column)->source;
  n_source_ids = DB_OBJ(index_column)->source_size / sizeof(grn_id);
  for (i = 0; i < n_source_ids; i++) {
    grn_id source_id = source_ids[i];
    if (source_id == indexed_column_id) {
      section = i + 1;
      break;
    }
  }

  return section;
}

static bool
grn_column_find_index_data_accessor_index_column(grn_ctx *ctx,
                                                 grn_accessor *a,
                                                 grn_find_index_data *data)
{
  grn_obj *index_column = a->obj;
  int section = 0;

  if (!grn_index_column_is_usable(ctx, index_column, data->op)) {
    return false;
  }

  /* Available patterns:
   *
   *   1. No section specified index: Index with section=0 is returned.
   *
   *      Example: select Memos --match_columns Tags.memos_tag
   *
   *        table_create Tags TABLE_HASH_KEY ShortText
   *        table_create Memos TABLE_HASH_KEY ShortText
   *        column_create Memos tag COLUMN_SCALAR Tags
   *        column_create Tags memos_tag COLUMN_INDEX Memos tag
   *
   *   2. Section specified index: Index with the specified section is returned.
   *
   *      Example: select Memos --match_columns Tags.memos_tag
   *
   *        table_create Memos TABLE_NO_KEY
   *        column_create Memos title COLUMN_SCALAR ShortText
   *        column_create Memos content COLUMN_SCALAR Text
   *        table_create Terms TABLE_PAT_KEY ShortText \
   *          --default_tokenizer TokenNgram \
   *          --normalizer NormalizerNFKC130
   *        column_create Terms memos \
   *          COLUMN_INDEX|WITH_POSITION|WITH_SECTION Memos title,content
   */

  if (a->next) {
    int specified_section;
    grn_bool is_invalid_section;
    if (a->next->next) {
      return false;
    }
    specified_section = find_section(ctx, index_column, a->next->obj);
    is_invalid_section = (specified_section == 0);
    if (is_invalid_section) {
      return false;
    }
    section = specified_section;
  }

  grn_find_index_data_refer(ctx, data, index_column);
  grn_find_index_data_found(ctx, data, index_column, section);

  return true;
}

static grn_bool
grn_column_find_index_data_accessor_is_key_search(grn_ctx *ctx,
                                                  grn_accessor *accessor,
                                                  grn_operator op)
{
  if (accessor->next) {
    return GRN_FALSE;
  }

  if (accessor->action != GRN_ACCESSOR_GET_KEY) {
    return GRN_FALSE;
  }

  if (!grn_obj_is_table(ctx, accessor->obj)) {
    return GRN_FALSE;
  }

  switch (op) {
  case GRN_OP_LESS:
  case GRN_OP_GREATER:
  case GRN_OP_LESS_EQUAL:
  case GRN_OP_GREATER_EQUAL:
  case GRN_OP_PREFIX:
    switch (accessor->obj->header.type) {
    case GRN_TABLE_PAT_KEY:
    case GRN_TABLE_DAT_KEY:
      return GRN_TRUE;
    default:
      return GRN_FALSE;
    }
  case GRN_OP_SUFFIX:
    return (accessor->obj->header.type == GRN_TABLE_PAT_KEY &&
            (accessor->obj->header.flags & GRN_OBJ_KEY_WITH_SIS));
  case GRN_OP_EQUAL:
  case GRN_OP_NOT_EQUAL:
    switch (accessor->obj->header.type) {
    case GRN_TABLE_HASH_KEY:
    case GRN_TABLE_PAT_KEY:
    case GRN_TABLE_DAT_KEY:
      return GRN_TRUE;
    default:
      return GRN_FALSE;
    }
  case GRN_OP_FUZZY:
    return (accessor->obj->header.type == GRN_TABLE_PAT_KEY);
  case GRN_OP_TERM_EXTRACT:
    switch (accessor->obj->header.type) {
    case GRN_TABLE_PAT_KEY:
    case GRN_TABLE_DAT_KEY:
      return true;
    default:
      return false;
    }
  default:
    return GRN_FALSE;
  }
}

static void
grn_column_find_index_data_accessor(grn_ctx *ctx,
                                    grn_obj *obj,
                                    grn_find_index_data *data)
{
  grn_accessor *a;
  int depth = 0;
  for (a = (grn_accessor *)obj; a; a = a->next, depth++) {
    grn_hook *hooks;
    bool found = false;
    bool nested_index = false;
    grn_hook_entry entry = (grn_hook_entry)-1;

    switch (a->action) {
    case GRN_ACCESSOR_GET_ID:
      if (!a->next) {
        found = true;
        grn_find_index_data_refer(ctx, data, obj);
        grn_find_index_data_found(ctx, data, obj, 0);
      }
      break;
    case GRN_ACCESSOR_GET_KEY:
      entry = GRN_HOOK_INSERT;
      break;
    case GRN_ACCESSOR_GET_COLUMN_VALUE:
      if (GRN_OBJ_INDEX_COLUMNP(a->obj)) {
        if (grn_column_find_index_data_accessor_index_column(ctx, a, data)) {
          return;
        }
        /* Available pattern: Nested index.
         *
         * Example: select Tags --match_columns memos_tag._key
         *
         *   table_create Tags TABLE_HASH_KEY ShortText
         *   table_create Memos TABLE_HASH_KEY ShortText
         *   column_create Memos tag COLUMN_SCALAR Tags
         *   column_create Tags memos_tag COLUMN_INDEX Memos tag
         *   table_create Terms TABLE_PAT_KEY ShortText    \
         *     --default_tokenizer TokenNgram              \
         *     --normalizer NormalizerNFKC130
         *   column_create Terms memos_key COLUMN_INDEX|WITH_POSITION Memos _key
         */
        nested_index = true;
      } else {
        entry = GRN_HOOK_SET;
      }
      break;
    default:
      break;
    }

    if (nested_index) {
      if (!grn_index_column_is_usable(ctx, a->obj, GRN_OP_EQUAL)) {
        break;
      }
      continue;
    }

    if (entry == (grn_hook_entry)-1) {
      break;
    }

    for (hooks = DB_OBJ(a->obj)->hooks[entry]; hooks; hooks = hooks->next) {
      grn_obj_default_set_value_hook_data *hook_data =
        (void *)GRN_NEXT_ADDR(hooks);
      grn_obj *target = grn_ctx_at(ctx, hook_data->target);

      if (!target) {
        report_hook_has_dangling_reference_error(ctx,
                                                 obj,
                                                 hook_data->target,
                                                 "[column][index]"
                                                 "[accessor][match]");
        continue;
      }
      grn_find_index_data_referred(ctx, data, target);

      if (target->header.type != GRN_COLUMN_INDEX) {
        continue;
      }
      if (a->next) {
        if (!grn_index_column_is_usable(ctx, target, GRN_OP_EQUAL)) {
          continue;
        }
      }

      found = GRN_TRUE;
      if (!a->next) {
        if (!grn_index_column_is_usable(ctx, target, data->op)) {
          continue;
        }

        int section = (MULTI_COLUMN_INDEXP(target)) ? hook_data->section : 0;
        if (depth == 0) {
          grn_find_index_data_found(ctx, data, target, section);
        } else {
          grn_find_index_data_refer(ctx, data, obj);
          grn_find_index_data_found(ctx, data, obj, section);
        }
      }
    }

    if (!found &&
        grn_column_find_index_data_accessor_is_key_search(ctx, a, data->op)) {
      grn_find_index_data_refer(ctx, data, obj);
      grn_find_index_data_found(ctx, data, obj, 0);
    }

    if (!found && a->next && grn_obj_is_table(ctx, a->obj)) {
      found = true;
    }

    if (!found) {
      break;
    }
  }
}

static void
grn_find_index_data_dispatch(grn_ctx *ctx,
                             grn_obj *obj,
                             grn_find_index_data *data)
{
  if (GRN_DB_OBJP(obj)) {
    switch (data->op) {
    case GRN_OP_EQUAL:
    case GRN_OP_NOT_EQUAL:
      grn_column_find_index_data_column_equal(ctx, obj, data);
      break;
    case GRN_OP_PREFIX:
    case GRN_OP_SUFFIX:
    case GRN_OP_MATCH:
    case GRN_OP_NEAR:
    case GRN_OP_NEAR_NO_OFFSET:
    case GRN_OP_NEAR_PHRASE:
    case GRN_OP_ORDERED_NEAR_PHRASE:
    case GRN_OP_NEAR_PHRASE_PRODUCT:
    case GRN_OP_ORDERED_NEAR_PHRASE_PRODUCT:
    case GRN_OP_SIMILAR:
    case GRN_OP_REGEXP:
    case GRN_OP_FUZZY:
    case GRN_OP_QUORUM:
      grn_column_find_index_data_column_match(ctx, obj, data);
      break;
    case GRN_OP_LESS:
    case GRN_OP_GREATER:
    case GRN_OP_LESS_EQUAL:
    case GRN_OP_GREATER_EQUAL:
    case GRN_OP_CALL:
      grn_column_find_index_data_column_range(ctx, obj, data);
      break;
    default:
      break;
    }
  } else if (GRN_ACCESSORP(obj)) {
    grn_column_find_index_data_accessor(ctx, obj, data);
  }
}

int
grn_column_index(grn_ctx *ctx,
                 grn_obj *obj,
                 grn_operator op,
                 grn_obj **index_buf,
                 int buf_size,
                 int *section_buf)
{
  GRN_API_ENTER;
  grn_find_index_data data;
  grn_find_index_data_init(ctx,
                           &data,
                           op,
                           NULL,
                           0,
                           index_buf,
                           buf_size,
                           section_buf);
  grn_find_index_data_dispatch(ctx, obj, &data);
  int n = data.n_found_indexes;
  grn_find_index_data_fin(ctx, &data);
  GRN_API_RETURN(n);
}

unsigned int
grn_column_find_index_data(grn_ctx *ctx,
                           grn_obj *obj,
                           grn_operator op,
                           grn_index_datum *index_data,
                           unsigned int n_index_data)
{
  GRN_API_ENTER;
  grn_find_index_data data;
  grn_find_index_data_init(ctx,
                           &data,
                           op,
                           index_data,
                           n_index_data,
                           NULL,
                           0,
                           NULL);
  grn_find_index_data_dispatch(ctx, obj, &data);
  unsigned int n = data.n_found_indexes;
  grn_find_index_data_fin(ctx, &data);
  GRN_API_RETURN(n);
}

static uint32_t
grn_column_get_all_index_data_column(grn_ctx *ctx,
                                     grn_obj *obj,
                                     grn_index_datum *index_data,
                                     uint32_t n_index_data,
                                     grn_obj *index_columns)
{
  uint32_t n = 0;
  grn_hook_entry hook_entry;
  grn_hook *hooks;

  switch (obj->header.type) {
  case GRN_TABLE_HASH_KEY:
  case GRN_TABLE_PAT_KEY:
  case GRN_TABLE_DAT_KEY:
  case GRN_TABLE_NO_KEY:
    hook_entry = GRN_HOOK_INSERT;
    break;
  default:
    hook_entry = GRN_HOOK_SET;
    break;
  }

  for (hooks = DB_OBJ(obj)->hooks[hook_entry]; hooks; hooks = hooks->next) {
    grn_obj_default_set_value_hook_data *data = (void *)GRN_NEXT_ADDR(hooks);
    grn_obj *target = grn_ctx_at(ctx, data->target);
    int section = 0;
    if (!target) {
      report_hook_has_dangling_reference_error(
        ctx,
        obj,
        data->target,
        "[column][indexes][all][column]");
      continue;
    }
    if (target->header.type != GRN_COLUMN_INDEX) {
      grn_obj_unref(ctx, target);
      continue;
    }
    if (!grn_obj_is_visible(ctx, target)) {
      grn_obj_unref(ctx, target);
      continue;
    }
    if (MULTI_COLUMN_INDEXP(target)) {
      section = data->section;
    }
    bool returned = false;
    if (n < n_index_data) {
      index_data[n].index = target;
      index_data[n].section = section;
      returned = true;
    }
    n++;
    if (index_columns) {
      GRN_PTR_PUT(ctx, index_columns, target);
      returned = true;
    }
    if (!returned) {
      grn_obj_unref(ctx, target);
    }
  }

  return n;
}

static uint32_t
grn_column_get_all_index_data_accessor_index_column(grn_ctx *ctx,
                                                    grn_accessor *a,
                                                    grn_index_datum *index_data,
                                                    uint32_t n_index_data,
                                                    grn_obj *index_columns)
{
  grn_obj *index_column = a->obj;
  int section = 0;

  if (a->next) {
    int specified_section;
    grn_bool is_invalid_section;
    if (a->next->next) {
      return 0;
    }
    specified_section = find_section(ctx, index_column, a->next->obj);
    is_invalid_section = (specified_section == 0);
    if (is_invalid_section) {
      return 0;
    }
    section = specified_section;
  }
  if (n_index_data > 0) {
    index_data[0].index = index_column;
    index_data[0].section = section;
  }
  if (index_columns) {
    GRN_PTR_PUT(ctx, index_columns, index_column);
  }

  return 1;
}

static uint32_t
grn_column_get_all_index_data_accessor(grn_ctx *ctx,
                                       grn_obj *obj,
                                       grn_index_datum *index_data,
                                       uint32_t n_index_data,
                                       grn_obj *index_columns)
{
  uint32_t n = 0;
  grn_accessor *a = (grn_accessor *)obj;

  while (a) {
    grn_hook *hooks;
    grn_bool found = GRN_FALSE;
    grn_hook_entry entry = (grn_hook_entry)-1;

    if (a->action == GRN_ACCESSOR_GET_COLUMN_VALUE &&
        GRN_OBJ_INDEX_COLUMNP(a->obj)) {
      return grn_column_get_all_index_data_accessor_index_column(ctx,
                                                                 a,
                                                                 index_data,
                                                                 n_index_data,
                                                                 index_columns);
    }

    switch (a->action) {
    case GRN_ACCESSOR_GET_KEY:
      entry = GRN_HOOK_INSERT;
      break;
    case GRN_ACCESSOR_GET_COLUMN_VALUE:
      entry = GRN_HOOK_SET;
      break;
    default:
      break;
    }

    if (entry == (grn_hook_entry)-1) {
      break;
    }

    for (hooks = DB_OBJ(a->obj)->hooks[entry]; hooks; hooks = hooks->next) {
      grn_obj_default_set_value_hook_data *data = (void *)GRN_NEXT_ADDR(hooks);
      grn_obj *target = grn_ctx_at(ctx, data->target);

      if (!target) {
        report_hook_has_dangling_reference_error(ctx,
                                                 obj,
                                                 data->target,
                                                 "[column][indexes]"
                                                 "[all][accessor]");
        continue;
      }
      if (target->header.type != GRN_COLUMN_INDEX) {
        continue;
      }
      if (!grn_obj_is_visible(ctx, target)) {
        continue;
      }

      found = GRN_TRUE;
      if (!a->next) {
        int section = 0;

        if (MULTI_COLUMN_INDEXP(target)) {
          section = data->section;
        }
        if (n < n_index_data) {
          index_data[n].index = target;
          index_data[n].section = section;
        }
        n++;
        if (index_columns) {
          GRN_PTR_PUT(ctx, index_columns, target);
        }
      }
    }

    if (!found) {
      break;
    }
    a = a->next;
  }

  return n;
}

uint32_t
grn_column_get_all_index_data(grn_ctx *ctx,
                              grn_obj *obj,
                              grn_index_datum *index_data,
                              uint32_t n_index_data)
{
  uint32_t n = 0;
  GRN_API_ENTER;
  if (GRN_DB_OBJP(obj)) {
    n = grn_column_get_all_index_data_column(ctx,
                                             obj,
                                             index_data,
                                             n_index_data,
                                             NULL);
  } else if (GRN_ACCESSORP(obj)) {
    n = grn_column_get_all_index_data_accessor(ctx,
                                               obj,
                                               index_data,
                                               n_index_data,
                                               NULL);
  }
  GRN_API_RETURN(n);
}

grn_rc
grn_column_get_all_index_columns(grn_ctx *ctx,
                                 grn_obj *obj,
                                 grn_obj *index_columns)
{
  GRN_API_ENTER;
  if (GRN_DB_OBJP(obj)) {
    grn_column_get_all_index_data_column(ctx, obj, NULL, 0, index_columns);
  } else if (GRN_ACCESSORP(obj)) {
    grn_column_get_all_index_data_accessor(ctx, obj, NULL, 0, index_columns);
  }
  GRN_API_RETURN(ctx->rc);
}

grn_rc
grn_column_get_all_token_columns(grn_ctx *ctx,
                                 grn_obj *obj,
                                 grn_obj *token_columns)
{
  GRN_API_ENTER;

  if (!GRN_DB_OBJP(obj)) {
    GRN_API_RETURN(ctx->rc);
  }

  grn_hook_entry hook_entry;
  switch (obj->header.type) {
  case GRN_TABLE_HASH_KEY:
  case GRN_TABLE_PAT_KEY:
  case GRN_TABLE_DAT_KEY:
  case GRN_TABLE_NO_KEY:
    hook_entry = GRN_HOOK_INSERT;
    break;
  default:
    hook_entry = GRN_HOOK_SET;
    break;
  }

  grn_hook *hooks;
  for (hooks = DB_OBJ(obj)->hooks[hook_entry]; hooks; hooks = hooks->next) {
    grn_obj_default_set_value_hook_data *data = (void *)GRN_NEXT_ADDR(hooks);
    grn_obj *target = grn_ctx_at(ctx, data->target);
    if (!target) {
      report_hook_has_dangling_reference_error(ctx,
                                               obj,
                                               data->target,
                                               "[column][token-columns][all]");
      continue;
    }
    if (target->header.type != GRN_COLUMN_VAR_SIZE) {
      grn_obj_unref(ctx, target);
      continue;
    }
    if (!grn_obj_is_visible(ctx, target)) {
      grn_obj_unref(ctx, target);
      continue;
    }
    GRN_PTR_PUT(ctx, token_columns, target);
  }

  GRN_API_RETURN(ctx->rc);
}

grn_rc
grn_column_get_all_hooked_columns(grn_ctx *ctx, grn_obj *obj, grn_obj *columns)
{
  GRN_API_ENTER;

  if (!GRN_DB_OBJP(obj)) {
    GRN_API_RETURN(ctx->rc);
  }

  grn_hook_entry hook_entry;
  switch (obj->header.type) {
  case GRN_TABLE_HASH_KEY:
  case GRN_TABLE_PAT_KEY:
  case GRN_TABLE_DAT_KEY:
  case GRN_TABLE_NO_KEY:
    hook_entry = GRN_HOOK_INSERT;
    break;
  default:
    hook_entry = GRN_HOOK_SET;
    break;
  }

  grn_hook *hooks;
  for (hooks = DB_OBJ(obj)->hooks[hook_entry]; hooks; hooks = hooks->next) {
    grn_obj_default_set_value_hook_data *data = (void *)GRN_NEXT_ADDR(hooks);
    grn_obj *target = grn_ctx_at(ctx, data->target);
    if (!target) {
      report_hook_has_dangling_reference_error(ctx,
                                               obj,
                                               data->target,
                                               "[column][hooked-columns][all]");
      continue;
    }
    if (!grn_obj_is_visible(ctx, target)) {
      grn_obj_unref(ctx, target);
      continue;
    }
    GRN_PTR_PUT(ctx, columns, target);
  }

  GRN_API_RETURN(ctx->rc);
}

grn_rc
grn_obj_columns(grn_ctx *ctx,
                grn_obj *table,
                const char *str,
                unsigned int str_size,
                grn_obj *res)
{
  grn_obj *col;
  const char *p = (char *)str, *q, *r, *pe = p + str_size, *tokbuf[256];
  while (p < pe) {
    int i, n = grn_tokenize(p, pe - p, tokbuf, 256, &q);
    for (i = 0; i < n; i++) {
      r = tokbuf[i];
      while (p < r && (' ' == *p || ',' == *p)) {
        p++;
      }
      if (p < r) {
        if (r[-1] == '*') {
          grn_hash *cols =
            grn_hash_create(ctx,
                            NULL,
                            sizeof(grn_id),
                            0,
                            GRN_OBJ_TABLE_HASH_KEY | GRN_HASH_TINY);
          if (cols) {
            grn_id *key;
            grn_table_columns(ctx, table, p, r - p - 1, (grn_obj *)cols);
            GRN_HASH_EACH(ctx, cols, id, &key, NULL, NULL, {
              if ((col = grn_ctx_at(ctx, *key))) {
                GRN_PTR_PUT(ctx, res, col);
              }
            });
            grn_hash_close(ctx, cols);
          }
          {
            grn_obj *type = grn_ctx_at(ctx, table->header.domain);
            if (GRN_OBJ_TABLEP(type)) {
              grn_obj *ai = grn_obj_column(ctx,
                                           table,
                                           GRN_COLUMN_NAME_ID,
                                           GRN_COLUMN_NAME_ID_LEN);
              if (ai) {
                if (ai->header.type == GRN_ACCESSOR) {
                  grn_accessor *id_accessor;
                  for (id_accessor = ((grn_accessor *)ai)->next; id_accessor;
                       id_accessor = id_accessor->next) {
                    grn_obj *target_table = id_accessor->obj;

                    cols =
                      grn_hash_create(ctx,
                                      NULL,
                                      sizeof(grn_id),
                                      0,
                                      GRN_OBJ_TABLE_HASH_KEY | GRN_HASH_TINY);
                    if (!cols) {
                      continue;
                    }

                    grn_table_columns(ctx,
                                      target_table,
                                      p,
                                      r - p - 1,
                                      (grn_obj *)cols);
                    GRN_HASH_EACH_BEGIN(ctx, cols, cursor, id)
                    {
                      void *key;
                      grn_hash_cursor_get_key(ctx, cursor, &key);
                      grn_id column_id = *((grn_id *)key);
                      col = grn_ctx_at(ctx, column_id);
                      if (!col) {
                        continue;
                      }

                      grn_accessor *a;
                      grn_accessor *ac;
                      ac = grn_accessor_new(ctx);
                      GRN_PTR_PUT(ctx, res, (grn_obj *)ac);
                      for (a = (grn_accessor *)ai; a; a = a->next) {
                        if (a != id_accessor) {
                          ac->action = a->action;
                          ac->obj = a->obj;
                          grn_obj_refer(ctx, ac->obj);
                          ac->next = grn_accessor_new(ctx);
                          if (!(ac = ac->next)) {
                            break;
                          }
                        } else {
                          ac->action = GRN_ACCESSOR_GET_COLUMN_VALUE;
                          ac->obj = col;
                          ac->next = NULL;
                          break;
                        }
                      }
                    }
                    GRN_HASH_EACH_END(ctx, cursor);
                    grn_hash_close(ctx, cols);
                  }
                }
                grn_obj_unlink(ctx, ai);
              }
            }
            grn_obj_unref(ctx, type);
          }
        } else if ((col = grn_obj_column(ctx, table, p, r - p))) {
          GRN_PTR_PUT(ctx, res, col);
        }
      }
      p = r;
    }
    p = q;
  }
  return ctx->rc;
}

grn_obj *
grn_table_column(grn_ctx *ctx,
                 grn_obj *table,
                 const char *name,
                 ssize_t name_size)
{
  GRN_API_ENTER;

  if (name_size < 0) {
    name_size = strlen(name);
  }

  grn_obj *column = grn_obj_column_(ctx, table, name, name_size);
  if (grn_obj_is_accessor(ctx, column)) {
    grn_obj_unlink(ctx, column);
    column = NULL;
  }

  GRN_API_RETURN(column);
}

grn_rc
grn_table_parse_load_columns(grn_ctx *ctx,
                             grn_obj *table,
                             const char *input,
                             size_t input_size,
                             grn_obj *columns)
{
  GRN_API_ENTER;
  const char *current = input;
  const char *end = input + input_size;
#define TOKEN_MAX 256
  const char *tokens[TOKEN_MAX];
  while (current < end) {
    const char *rest;
    int n = grn_tokenize(current, end - current, tokens, TOKEN_MAX, &rest);
    int i;
    for (i = 0; i < n; i++) {
      const char *next_start = tokens[i];
      while (current < next_start && (' ' == *current || ',' == *current)) {
        current++;
      }
      if (current < next_start) {
        grn_raw_string column_name;
        column_name.value = current;
        column_name.length = next_start - current;
        if (column_name.value[0] == '_') {
          if (grn_obj_is_table_with_key(ctx, table) &&
              GRN_RAW_STRING_EQUAL_CSTRING(column_name, GRN_COLUMN_NAME_KEY)) {
            grn_accessor *key_accessor = grn_accessor_new_key(ctx, table);
            if (key_accessor) {
              GRN_PTR_PUT(ctx, columns, key_accessor);
            }
          }
        } else {
          grn_obj *column =
            grn_table_column(ctx, table, current, next_start - current);
          if (column) {
            GRN_PTR_PUT(ctx, columns, column);
          }
        }
      }
      current = next_start;
    }
    current = rest;
  }
#undef TOKEN_MAX
  GRN_API_RETURN(ctx->rc);
}

bool
grn_table_is_grouped(grn_ctx *ctx, grn_obj *table)
{
  if (GRN_OBJ_TABLEP(table) && GRN_TABLE_IS_GROUPED(table)) {
    return true;
  }
  return false;
}

unsigned int
grn_table_max_n_subrecs(grn_ctx *ctx, grn_obj *table)
{
  if (GRN_OBJ_TABLEP(table)) {
    return DB_OBJ(table)->max_n_subrecs;
  }
  return 0;
}

grn_obj *
grn_table_tokenize(grn_ctx *ctx,
                   grn_obj *table,
                   const char *str,
                   unsigned int str_len,
                   grn_obj *buf,
                   bool addp)
{
  grn_token_cursor *token_cursor = NULL;
  grn_tokenize_mode mode = addp ? GRN_TOKENIZE_ADD : GRN_TOKENIZE_GET;
  GRN_API_ENTER;
  if (!(token_cursor =
          grn_token_cursor_open(ctx, table, str, str_len, mode, 0))) {
    goto exit;
  }
  if (buf) {
    GRN_BULK_REWIND(buf);
  } else {
    if (!(buf = grn_obj_open(ctx, GRN_UVECTOR, 0, DB_OBJ(table)->id))) {
      goto exit;
    }
  }
  while (token_cursor->status != GRN_TOKEN_CURSOR_DONE &&
         token_cursor->status != GRN_TOKEN_CURSOR_DONE_SKIP) {
    grn_id tid;
    if ((tid = grn_token_cursor_next(ctx, token_cursor))) {
      GRN_RECORD_PUT(ctx, buf, tid);
    }
  }
exit:
  if (token_cursor) {
    grn_token_cursor_close(ctx, token_cursor);
  }
  GRN_API_RETURN(buf);
}

static void
grn_db_recover_database_remove_orphan_inspect(grn_ctx *ctx, grn_obj *db)
{
  GRN_TABLE_EACH_BEGIN_FLAGS(ctx, db, cursor, id, GRN_CURSOR_BY_ID)
  {
    void *key;
    int key_size;

    key_size = grn_table_cursor_get_key(ctx, cursor, &key);
#define INSPECT     "inspect"
#define INSPECT_LEN (sizeof(INSPECT) - 1)
    if (key_size == INSPECT_LEN && memcmp(key, INSPECT, INSPECT_LEN) == 0) {
      if (!grn_ctx_at(ctx, id)) {
        ERRCLR(ctx);
        grn_obj_delete_by_id(ctx, db, id, GRN_TRUE);
        GRN_LOG(ctx,
                GRN_LOG_INFO,
                "[db][recover] removed orphan 'inspect' object: <%u>",
                id);
      }
      break;
    }
#undef INSPECT
#undef INSPECT_LEN
  }
  GRN_TABLE_EACH_END(ctx, cursor);
}

static void
grn_db_recover_database(grn_ctx *ctx, grn_obj *db)
{
  if (grn_obj_is_locked(ctx, db)) {
    ERR(GRN_OBJECT_CORRUPT,
        "[db][recover] database may be broken. Please re-create the database");
    return;
  }

  grn_db_clear_dirty(ctx, db);
  grn_db_recover_database_remove_orphan_inspect(ctx, db);
}

static bool
grn_db_recover_table_is_broken(grn_ctx *ctx, grn_obj *table)
{
  if (grn_obj_is_locked(ctx, table)) {
    return true;
  }

  if (grn_obj_is_table_with_key(ctx, table) &&
      grn_table_have_duplicated_keys(ctx, table)) {
    return true;
  }

  return false;
}

static void
grn_db_recover_table(grn_ctx *ctx, grn_obj *table)
{
  if (!grn_db_recover_table_is_broken(ctx, table)) {
    return;
  }

  if (grn_obj_is_lexicon_without_data_column(ctx, table)) {
    grn_table_truncate(ctx, table);
    grn_obj_reindex(ctx, table);
  } else {
    char name[GRN_TABLE_MAX_KEY_SIZE];
    unsigned int name_size;
    name_size = grn_obj_name(ctx, table, name, GRN_TABLE_MAX_KEY_SIZE);
    ERR(GRN_OBJECT_CORRUPT,
        "[db][recover] table may be broken: <%.*s>: "
        "please truncate the table (or clear lock of the table) "
        "and load data again",
        (int)name_size,
        name);
  }
}

static void
grn_db_recover_data_column(grn_ctx *ctx, grn_obj *data_column)
{
  if (!grn_obj_is_locked(ctx, data_column)) {
    return;
  }

  {
    char name[GRN_TABLE_MAX_KEY_SIZE];
    unsigned int name_size;
    name_size = grn_obj_name(ctx, data_column, name, GRN_TABLE_MAX_KEY_SIZE);
    ERR(GRN_OBJECT_CORRUPT,
        "[db][recover] column may be broken: <%.*s>: "
        "please truncate the column (or clear lock of the column) "
        "and load data again",
        (int)name_size,
        name);
  }
}

static void
grn_db_recover_index_column(grn_ctx *ctx, grn_obj *index_column)
{
  if (!grn_obj_is_locked(ctx, index_column)) {
    return;
  }

  grn_index_column_rebuild(ctx, index_column);
}

static grn_bool
grn_db_recover_is_builtin(grn_ctx *ctx, grn_id id, grn_table_cursor *cursor)
{
  void *key;
  const char *name;
  int name_size;

  if (id < GRN_N_RESERVED_TYPES) {
    return GRN_TRUE;
  }

  name_size = grn_table_cursor_get_key(ctx, cursor, &key);
  name = key;

#define NAME_EQUAL(value)                                                      \
  (name_size == strlen(value) && memcmp(name, value, strlen(value)) == 0)

  if (NAME_EQUAL("inspect")) {
    /* Just for compatibility. It's needed for users who used
       Groonga master at between 2016-02-03 and 2016-02-26. */
    return GRN_TRUE;
  }

#undef NAME_EQUAL

  return GRN_FALSE;
}

grn_rc
grn_db_recover(grn_ctx *ctx, grn_obj *db)
{
  grn_table_cursor *cursor;
  grn_id id;
  grn_bool is_close_opened_object_mode;

  GRN_API_ENTER;

  is_close_opened_object_mode = (grn_thread_get_limit() == 1);

  grn_db_recover_database(ctx, db);
  if (ctx->rc != GRN_SUCCESS) {
    GRN_API_RETURN(ctx->rc);
  }

  cursor =
    grn_table_cursor_open(ctx, db, NULL, 0, NULL, 0, 0, -1, GRN_CURSOR_BY_ID);
  if (!cursor) {
    GRN_API_RETURN(ctx->rc);
  }

  while ((id = grn_table_cursor_next(ctx, cursor)) != GRN_ID_NIL) {
    grn_obj *object;

    if (is_close_opened_object_mode) {
      grn_ctx_push_temporary_open_space(ctx);
    }

    if ((object = grn_ctx_at(ctx, id))) {
      switch (object->header.type) {
      case GRN_TABLE_NO_KEY:
      case GRN_TABLE_HASH_KEY:
      case GRN_TABLE_PAT_KEY:
      case GRN_TABLE_DAT_KEY:
        grn_db_recover_table(ctx, object);
        break;
      case GRN_COLUMN_FIX_SIZE:
      case GRN_COLUMN_VAR_SIZE:
        grn_db_recover_data_column(ctx, object);
        break;
      case GRN_COLUMN_INDEX:
        grn_db_recover_index_column(ctx, object);
        break;
      default:
        break;
      }
      grn_obj_unlink(ctx, object);
    } else {
      if (grn_db_recover_is_builtin(ctx, id, cursor)) {
        ERRCLR(ctx);
      }
    }

    if (is_close_opened_object_mode) {
      grn_ctx_pop_temporary_open_space(ctx);
    }

    if (ctx->rc != GRN_SUCCESS) {
      break;
    }
  }
  grn_table_cursor_close(ctx, cursor);

  GRN_API_RETURN(ctx->rc);
}

grn_rc
grn_db_unmap(grn_ctx *ctx, grn_obj *db)
{
  grn_db *s = (grn_db *)db;

  GRN_API_ENTER;

  GRN_TINY_ARRAY_EACH_BEGIN(&s->values, 1, grn_db_curr_id(ctx, db), value)
  {
    db_value *vp = value;
    grn_obj *obj = vp->ptr;

    if (obj) {
      switch (obj->header.type) {
      case GRN_COLUMN_FIX_SIZE:
      case GRN_COLUMN_VAR_SIZE:
      case GRN_COLUMN_INDEX:
        grn_obj_close(ctx, obj);
        break;
      }
    }
  }
  GRN_TINY_ARRAY_EACH_END();

  GRN_TINY_ARRAY_EACH_BEGIN(&s->values, 1, grn_db_curr_id(ctx, db), value)
  {
    db_value *vp = value;
    grn_obj *obj = vp->ptr;

    if (obj) {
      switch (obj->header.type) {
      case GRN_TABLE_HASH_KEY:
      case GRN_TABLE_PAT_KEY:
      case GRN_TABLE_DAT_KEY:
      case GRN_TABLE_NO_KEY:
        grn_obj_close(ctx, obj);
        break;
      }
    }
  }
  GRN_TINY_ARRAY_EACH_END();

  GRN_API_RETURN(ctx->rc);
}

static grn_rc
grn_ctx_get_all_objects(grn_ctx *ctx,
                        grn_obj *objects_buffer,
                        grn_bool (*predicate)(grn_ctx *ctx, grn_obj *object))
{
  grn_obj *db;
  grn_table_cursor *cursor;
  grn_id id;

  GRN_API_ENTER;

  db = ctx->impl->db;
  if (!db) {
    ERR(GRN_INVALID_ARGUMENT, "DB isn't associated");
    GRN_API_RETURN(ctx->rc);
  }

  cursor = grn_table_cursor_open(ctx, db, NULL, 0, NULL, 0, 0, -1, 0);
  if (!cursor) {
    GRN_API_RETURN(ctx->rc);
  }

  while ((id = grn_table_cursor_next(ctx, cursor)) != GRN_ID_NIL) {
    grn_obj *object;

    if ((object = grn_ctx_at(ctx, id))) {
      if (predicate(ctx, object)) {
        GRN_PTR_PUT(ctx, objects_buffer, object);
      } else {
        grn_obj_unlink(ctx, object);
      }
    } else {
      if (ctx->rc != GRN_SUCCESS) {
        ERRCLR(ctx);
      }
    }
  }
  grn_table_cursor_close(ctx, cursor);

  GRN_API_RETURN(ctx->rc);
}

grn_rc
grn_ctx_get_all_tables(grn_ctx *ctx, grn_obj *tables_buffer)
{
  return grn_ctx_get_all_objects(ctx, tables_buffer, grn_obj_is_table);
}

grn_rc
grn_ctx_get_all_types(grn_ctx *ctx, grn_obj *types_buffer)
{
  return grn_ctx_get_all_objects(ctx, types_buffer, grn_obj_is_type);
}

grn_rc
grn_ctx_get_all_tokenizers(grn_ctx *ctx, grn_obj *tokenizers_buffer)
{
  return grn_ctx_get_all_objects(ctx,
                                 tokenizers_buffer,
                                 grn_obj_is_tokenizer_proc);
}

grn_rc
grn_ctx_get_all_normalizers(grn_ctx *ctx, grn_obj *normalizers_buffer)
{
  return grn_ctx_get_all_objects(ctx,
                                 normalizers_buffer,
                                 grn_obj_is_normalizer_proc);
}

grn_rc
grn_ctx_get_all_token_filters(grn_ctx *ctx, grn_obj *token_filters_buffer)
{
  return grn_ctx_get_all_objects(ctx,
                                 token_filters_buffer,
                                 grn_obj_is_token_filter_proc);
}

grn_rc
grn_ctx_push_temporary_open_space(grn_ctx *ctx)
{
  grn_obj *stack;
  grn_obj *space;
  grn_obj buffer;

  if (grn_enable_reference_count) {
    return ctx->rc;
  }

  GRN_API_ENTER;

  stack = &(ctx->impl->temporary_open_spaces.stack);
  GRN_VOID_INIT(&buffer);
  grn_bulk_write(ctx, stack, (const char *)&buffer, sizeof(grn_obj));
  space = ((grn_obj *)GRN_BULK_CURR(stack)) - 1;
  GRN_PTR_INIT(space, GRN_OBJ_VECTOR | GRN_OBJ_OWN, GRN_ID_NIL);

  ctx->impl->temporary_open_spaces.current = space;

  GRN_API_RETURN(ctx->rc);
}

grn_rc
grn_ctx_pop_temporary_open_space(grn_ctx *ctx)
{
  grn_obj *stack;
  grn_obj *space;

  if (grn_enable_reference_count) {
    return ctx->rc;
  }

  GRN_API_ENTER;

  stack = &(ctx->impl->temporary_open_spaces.stack);
  if (GRN_BULK_EMPTYP(stack)) {
    ERR(GRN_INVALID_ARGUMENT, "[ctx][temporary-open-spaces][pop] too much pop");
    GRN_API_RETURN(ctx->rc);
  }

  space = ctx->impl->temporary_open_spaces.current;
  GRN_OBJ_FIN(ctx, space);
  grn_bulk_truncate(ctx, stack, GRN_BULK_VSIZE(stack) - sizeof(grn_obj));

  if (GRN_BULK_EMPTYP(stack)) {
    space = NULL;
  } else {
    space = ((grn_obj *)GRN_BULK_CURR(stack)) - 1;
  }
  ctx->impl->temporary_open_spaces.current = space;

  GRN_API_RETURN(ctx->rc);
}

grn_rc
grn_ctx_merge_temporary_open_space(grn_ctx *ctx)
{
  grn_obj *stack;
  grn_obj *space;
  grn_obj *next_space;

  if (grn_enable_reference_count) {
    return ctx->rc;
  }

  GRN_API_ENTER;

  stack = &(ctx->impl->temporary_open_spaces.stack);
  if (GRN_BULK_VSIZE(stack) < sizeof(grn_obj) * 2) {
    ERR(GRN_INVALID_ARGUMENT,
        "[ctx][temporary-open-spaces][merge] "
        "merge requires at least two spaces");
    GRN_API_RETURN(ctx->rc);
  }

  space = ctx->impl->temporary_open_spaces.current;
  next_space = ctx->impl->temporary_open_spaces.current - 1;
  {
    unsigned int i, n_elements;
    n_elements = GRN_PTR_VECTOR_SIZE(space);
    for (i = 0; i < n_elements; i++) {
      grn_obj *element = GRN_PTR_VALUE_AT(space, i);
      GRN_PTR_PUT(ctx, next_space, element);
    }
  }
  GRN_BULK_REWIND(space);
  GRN_OBJ_FIN(ctx, space);
  grn_bulk_truncate(ctx, stack, GRN_BULK_VSIZE(stack) - sizeof(grn_obj));

  if (GRN_BULK_EMPTYP(stack)) {
    space = NULL;
  } else {
    space = ((grn_obj *)GRN_BULK_CURR(stack)) - 1;
  }
  ctx->impl->temporary_open_spaces.current = space;

  GRN_API_RETURN(ctx->rc);
}
