On 6/4/05, Dmitry Yemanov <dimitr@...> wrote:

> "Ann W. Harrison" <aharrison@...> wrote:
> >
> > >
> > > I'm pretty sure PG used a hash aggregate which really performs better
> than a
> > > sort aggregate.
> >
> > Ok, thanks, I thought there was something like that.
>
> Well, it doesn't make big difference. I've performed a quick test with FB
> 1.5.2 and PG 8.0 on win32. On second run FB is faster than PG, except the
> GROUP BY clause (where PG slightly wins). But the first run (when our page
> cache is empty) makes a very big difference: PG is about 20x faster than FB.
> I don't believe in miracles, so I suspect some in advance database caching
> on the PG side, but neither of the PG backend processes occupied more than
> 10MB of RAM whilst the test table was 50M. I think this should be
> investigated a bit further.
>
>
> Dmitry

Thumbs up for your response Dmitry