Skip site navigation (1) Skip section navigation (2)

Re: bitmap-index-scan slower than normal index scan

From: "Alex Deucher" <alexdeucher(at)gmail(dot)com>
To: "A(dot) Kretschmer" <andreas(dot)kretschmer(at)schollglas(dot)com>
Cc: pgsql-performance(at)postgresql(dot)org
Subject: Re: bitmap-index-scan slower than normal index scan
Date: 2007-07-11 20:01:30
Message-ID: a728f9f90707111301r31f6fa25mf4e5405f264bdf10@mail.gmail.com (view raw or flat)
Thread:
Lists: pgsql-performance
On 7/11/07, A. Kretschmer <andreas(dot)kretschmer(at)schollglas(dot)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

In response to

Responses

pgsql-performance by date

Next:From: Alex DeucherDate: 2007-07-11 20:01:58
Subject: Re: bitmap-index-scan slower than normal index scan
Previous:From: Joshua D. DrakeDate: 2007-07-11 19:45:29
Subject: Re: WALL on controller without battery?

Privacy Policy | About PostgreSQL
Copyright © 1996-2014 The PostgreSQL Global Development Group