2.2.5.4 QueryHint

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Namespace: http://schemas.datacontract.org/2004/07/Microsoft.Office.Server.Search.Query

The QueryHint simple type is used to represent how the protocol server processes a search query.

 <xs:simpleType name="QueryHint" xmlns:xs="http://www.w3.org/2001/XMLSchema">
   <xs:list>
     <xs:simpleType>
       <xs:restriction base="xs:string">
         <xs:enumeration value="None"/>
         <xs:enumeration value="OptimizeWithFullTextIndex"/>
         <xs:enumeration value="OptimizeWithPropertyStore"/>
         <xs:enumeration value="PropertySelectWithInClause"/>
         <xs:enumeration value="PropertySelectWithTempTable"/>
         <xs:enumeration value="UseSqlFirstJoinStrategy"/>
         <xs:enumeration value="AvoidSqlOuterJoins"/>
       </xs:restriction>
     </xs:simpleType>
   </xs:list>
 </xs:simpleType>

The following table specifies the allowable values for the QueryHint simple type.

Value	Meaning
None	The protocol server MUST determine whether to use the metadata index or the full-text index catalog first when processing a query.
OptimizeWithFullTextIndex	The protocol server MUST use the full-text index catalog first when processing a query.
OptimizeWithPropertyStore	The protocol server MUST use the metadata index first when processing a query.
PropertySelectWithInClause	Obsolete.
PropertySelectWithTempTable	Obsolete.
UseSqlFirstJoinStrategy	The protocol server MUST use the metadata index first when it guarantees correctness of the results. Otherwise, MUST use the full-text index.
AvoidSqlOuterJoins	The protocol server MUST NOT use outer joins when processing a query.