"W.Alphonse HAROUNY" <[EMAIL PROTECTED]> writes: > Question: > -------------- > I have an SQL request similar to: > > SELECT ..... FROM TBL1, TBL2 WHERE > <inner join between TBL1 and TBL2 is True> AND > TBL1.CATEGORY & TBL2.CATEGORY <> 0 //-- where & is the AND bitwise > operator > > Qst: > 1/ IS the above SQL request will use the INDEX [categoryGroup] defined on > TBL1 and TBL2 ?
No, & isn't an indexable operator for any of the standard indexing methods. You could create 32 partial indexes on some other key with clauses like WHERE tbl1.category & 0100... = 0100... But I don't think that would be useful for a join clause in any case. Second idea, you could create an expression index on tbl1 (category & 0100... = 0100..., category & 0010... = 0010..., category & 0001... = 0001..., ...) Again I don't see that it's going to be used for a join condition. Lastly, you could look for a GIST index method for varbit which would be superior to both of the above tactics. I'm still not sure it would be able to handle a join clause though, but maybe? -- Gregory Stark EnterpriseDB http://www.enterprisedb.com ---------------------------(end of broadcast)--------------------------- TIP 9: In versions below 8.0, the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match