Oleg Bartunov <oleg(at)sai(dot)msu(dot)su> writes:
> The best plan I've got eliminating IN predicate:
> select msg_prt.tid as mid from msg_prt
> where exists (select idx.tid from idx where msg_prt.tid=idx.tid
> and idx.did=1 and idx.lid = 1207 and idx.lid=59587 )
Surely that returns zero rows?
regards, tom lane