"Michael Nolan" <htfoot@xxxxxxxxx> writes: > select count(*) from memmast where memid in (select plr_rated_memid from > tnmt_plr where plr_eventid in ('200607163681'); > This query takes about a second on PostgreSQL but takes OVER SEVEN MINUTES > on MySQL! Yeah, and we probably would have sucked about as badly before 7.4 or so. There's a long way from "having subselects" to being able to optimize them decently. AFAIK mysql is still at the "we've got subselects!" stage ... regards, tom lane