Primoz <primoz@slo-tech.com> writes:
> is there any way to speedup queryes like
> select ... from [table a] where [int field b] = [number] order by [datetime
> field c] desc limit [number];
For reasonably-small values of the LIMIT, what you want is
(a) a two-column index on (b,c)
(b) change the ORDER BY to
ORDER BY b DESC, c DESC
See the pgsql-performance archives for more discussion.
regards, tom lane