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To: Brian Herlihy <btherl@yahoo.com.au>
cc: Postgresql Performance <pgsql-performance@postgresql.org>
Subject: Re: An unwanted seqscan 
In-reply-to: <379816.98018.qm@web52311.mail.yahoo.com> 
References: <379816.98018.qm@web52311.mail.yahoo.com>
Comments: In-reply-to Brian Herlihy <btherl@yahoo.com.au>
	message dated "Wed, 14 Feb 2007 00:40:13 -0800"
Date: Wed, 14 Feb 2007 03:53:54 -0500
Message-ID: <20031.1171443234@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
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Brian Herlihy <btherl@yahoo.com.au> writes:
> I am having trouble understanding why a seqscan is chosen for this query.

As far as anyone can see from this output, the planner's decisions are
correct: it prefers the plans with the smaller estimated cost.  If you
want us to take an interest, provide some more context --- EXPLAIN
ANALYZE output for starters.

			regards, tom lane