From: A. Kretschmer <andreas.kretschmer@schollglas.com>
To: pgsql-sql@postgresql.org
Subject: many 'OR' in WHERE-condition
Date: Fri, 20 Apr 2007 07:13:42 +0200
Message-ID: <20070420051341.GA15322@a-kretschmer.de> (raw)
Hello,
a friend of mine has got a problem:
in a SELECT with a condition 'WHERE foo IN (1,2,3,4,...)' with a large
list within. The optimizer choose a rewrite to many OR's and a bitmap
index scan on the index, no problem, fast.
But if the list increase the planner choose an seq-scan. The amount of
values in the list is about 200 and the table has about 250.000 rows.
How can we avoid the seq-scan?
Andreas, thx in advance.
--
Andreas Kretschmer
Kontakt: Heynitz: 035242/47150, D1: 0160/7141639 (mehr: -> Header)
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To: pgsql-sql@postgresql.org
Cc: andreas.kretschmer@schollglas.com
Subject: Re: many 'OR' in WHERE-condition
In-Reply-To: <20070420051341.GA15322@a-kretschmer.de>
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