Maybe explain analyze select count(distinct a.subsno ) from subsexpired a where a.subsno not in (select b.subsno from subs b where b.subsno>75043 and b.subsno<=112565) and a.subsno>75043 and a.subsno<=112565;
Give you more information about real excecuting time. About postgres.conf checkpoint_segments = 64 Gabriel. On Fri, Dec 14, 2012 at 4:23 PM, Shams Khan <shams.kha...@gmail.com> wrote: > explain select count(distinct a.subsno ) from subsexpired a where > a.subsno not in (select b.subsno from subs b where b.subsno>75043 and > b.subsno<=112565) and a.subsno>75043 and a.subsno<=112565;