On Mon, Aug 30, 2004 at 21:21:26 +0200, Pierre-Frédéric Caillaud <[EMAIL PROTECTED]> wrote: > >>Also, count(*) is likely to always generate a seq scan due to the way > >>aggregates are implemented currently in pgsql. you might want to try: > > > By the way, in an ideal world, count(*) should only read the index > on the timetamp column, not the rows. I guess this is not the case. Would > this be an useful optimization ?
It's in the archives. The short answer is that no, postgres has to check the heap to check tuple visibility to the current transaction. ---------------------------(end of broadcast)--------------------------- TIP 5: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faqs/FAQ.html