<sparql
 xmlns="http://www.w3.org/2005/sparql-results#">
   <head>
      <variable
       name="x1" />
      <variable
       name="v1" />
      <variable
       name="x2" />
      <variable
       name="v2" />
   </head>
   <results
   
   >
      <result>
         <binding
          name="x1">
            <uri>http://example/x1</uri>
         </binding>
         <binding
          name="v1">
            <literal>xyz</literal>
         </binding>
         <binding
          name="x2">
            <uri>http://example/x4</uri>
         </binding>
         <binding
          name="v2">
            <literal
             datatype="http://www.w3.org/2001/XMLSchema#string">xyz</literal>
         </binding>
      </result>
      <result>
         <binding
          name="x1">
            <uri>http://example/x4</uri>
         </binding>
         <binding
          name="v1">
            <literal
             datatype="http://www.w3.org/2001/XMLSchema#string">xyz</literal>
         </binding>
         <binding
          name="x2">
            <uri>http://example/x1</uri>
         </binding>
         <binding
          name="v2">
            <literal>xyz</literal>
         </binding>
      </result>
   </results>
</sparql>

