Set grouping attribute

# SphinxClient::setGroupBy

(PECL sphinx >= 0.1.0)

SphinxClient::setGroupBy — Set grouping attribute

### 説明

public SphinxClient::setGroupBy ( string `$attribute` , int `$func` [, string `$groupsort` = "@group desc" ] ) : bool

Sets grouping attribute, function, and group sorting mode, and enables grouping.

Grouping feature is very similar to GROUP BY clause in SQL. Results produced by this function call are going to be the same as produced by the following pseudo code: SELECT ... GROUP BY $func($attribute) ORDER BY $groupsort.

### パラメータ

`attribute`

  A string containing group-by attribute name.

`func`

  Constant, which sets a function applied to the attribute value in order to compute group-by key.

`groupsort`

  An optional clause controlling how the groups are sorted.

### 返り値

成功した場合に `TRUE` を、失敗した場合に `FALSE` を返します。

### 参考

- SphinxClient::resetGroupBy
- SphinxClient::setSortMode
- SphinxClient::setGroupDistinct