From: Alex Deucher <alexdeucher@gmail.com>
To: A. Kretschmer <andreas.kretschmer@schollglas.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: bitmap-index-scan slower than normal index scan
Date: Wed, 11 Jul 2007 16:01:30 -0400
Message-ID: <a728f9f90707111301r31f6fa25mf4e5405f264bdf10@mail.gmail.com> (raw)
In-Reply-To: <20070711193158.GA28352@a-kretschmer.de>
References: <20070711183638.GA30872@KanotixBox>
<a728f9f90707111152w5e6d7316md4df25c33965c5d4@mail.gmail.com>
<20070711193158.GA28352@a-kretschmer.de>
On 7/11/07, A. Kretschmer <andreas.kretschmer@schollglas.com> wrote:
> am Wed, dem 11.07.2007, um 14:52:01 -0400 mailte Alex Deucher folgendes:
> > >Okay, i got a really different plan, but i expected _NOT_ a
> > >performance-boost like this. I expected the opposite.
> > >
> > >
> > >It's not a really problem, i just played with this. But i'm confused
> > >about this...
> > >
> >
> > your results are getting cached. try two queries in a row with the same
> > plan.
>
> Thanks for the response, but I've done this, no difference.
>
try bumping up the default stats target on the table in question and
see if that helps the planner choose a better plan.
Alex
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To: pgsql-performance@postgresql.org
Cc: alexdeucher@gmail.com, andreas.kretschmer@schollglas.com
Subject: Re: bitmap-index-scan slower than normal index scan
In-Reply-To: <a728f9f90707111301r31f6fa25mf4e5405f264bdf10@mail.gmail.com>
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