INM1=# explain select ref_num from grls where ag_id in (24); Index Scan using grls_ag_id on grls (cost=0.00..597.87 rows=849 width=12) IMN1=# explain select ref_num from grls where ag_id in (select 24); Seq Scan on grls (cost=0.00..992.44 rows=30195 width=12) SubPlan -> Materialize (cost=0.00..0.00 rows=0 width=0) -> Result (cost=0.00..0.00 rows=0 width=0) IMN1=# explain select ref_num from grls where ag_id = (select 24); Index Scan using grls_ag_id on grls (cost=0.00..597.87 rows=849 width=12) InitPlan -> Result (cost=0.00..0.00 rows=0 width=0) ". . . in (24) " work in 35 faster than ". . . in (select 24)". In the last don't use indices for increase perfomans. It's been normaly work in PostgreSQL version 7.2 ? Or not? P.S. Sorry my English. ---------------------------(end of broadcast)--------------------------- TIP 3: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to [EMAIL PROTECTED] so that your message can get through to the mailing list cleanly