Tom, I'm using 8.3.1. I did run EXPLAIN but have never familiarized myself with how to read/use it beside simple comparing cost estimation and whether there is any seq scan that can benefit from creating index. Thanks for replying On Jun 7, 11:19 am, t...@xxxxxxxxxxxxx (Tom Lane) wrote: > askel <dummy...@xxxxxxx> writes: > > Performance is at least few times better when EXISTS is used. > > It really shouldn't be. PG knows more possible plans for IN than > EXISTS, so IN should pretty much always be equal or better ... unless > the planner is making the wrong choice. I speculate that you have > out-of-date statistics or some such. Have you compared EXPLAIN ANALYZE > output for the two cases? Which PG version are we talking about? > > regards, tom lane > > -- > Sent via pgsql-general mailing list (pgsql-gene...@xxxxxxxxxxxxxx) > To make changes to your subscription:http://www.postgresql.org/mailpref/pgsql-general