From: Josh Berkus <josh@agliodbs.com>
To: pgsql-hackers@postgresql.org
Cc: Merlin Moncure <merlin.moncure@rcsonline.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: [HACKERS] bitmap scan issues 8.1 devel
Date: Wed, 17 Aug 2005 14:33:15 -0700
Message-ID: <200508171433.15614.josh@agliodbs.com> (raw)
In-Reply-To: <6EE64EF3AB31D5448D0007DD34EEB3417DD11C@Herge.rcsinc.local>
References: <6EE64EF3AB31D5448D0007DD34EEB3417DD11C@Herge.rcsinc.local>
Merlin,
> -> Index Scan using product_structure_file_pkey on
> product_structure_file (cost=0.00..45805.23 rows=5722 width=288)
> (actual time=0.063..0.063 row
> s=1 loops=1)
It appears that your DB is estimating the number of rows returned much too
high (5722 instead of 1). Please raise the statistics on all columns to
about 500, analyze, and try your test again.
Thanks!
--
--Josh
Josh Berkus
Aglio Database Solutions
San Francisco
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To: pgsql-performance@postgresql.org
Cc: josh@agliodbs.com, pgsql-hackers@postgresql.org, merlin.moncure@rcsonline.com
Subject: Re: [HACKERS] bitmap scan issues 8.1 devel
In-Reply-To: <200508171433.15614.josh@agliodbs.com>
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