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To: Brian Herlihy <btherl@yahoo.com.au>
cc: Postgresql Performance <pgsql-performance@postgresql.org>
Subject: Re: Join vs Subquery 
In-reply-to: <243066.5712.qm@web52308.mail.re2.yahoo.com> 
References: <243066.5712.qm@web52308.mail.re2.yahoo.com>
Comments: In-reply-to Brian Herlihy <btherl@yahoo.com.au>
	message dated "Wed, 02 May 2007 23:07:57 -0700"
Date: Thu, 03 May 2007 10:23:42 -0400
Message-ID: <3608.1178202222@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
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Brian Herlihy <btherl@yahoo.com.au> writes:
> The issue: the second query results in a lower cost estimate.  I am wondering why the second query plan was not chosen for the first query.

8.1 is incapable of pushing indexable join conditions down below an Append.
Try 8.2.

			regards, tom lane