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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Dave Cramer <pg@fastcrypt.com>
cc: pgsql-performance <pgsql-performance@postgresql.org>
Subject: Re: performance regression with 9.2
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Comments: In-reply-to Dave Cramer <pg@fastcrypt.com>
	message dated "Mon, 12 Nov 2012 14:49:00 -0500"
Date: Mon, 12 Nov 2012 15:43:53 -0500
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Dave Cramer <pg@fastcrypt.com> writes:
> This query is a couple orders of magnitude slower the first result is
> 9.2.1, the second 9.1

Hm, the planner's evidently doing the wrong thing inside the recursive
union, but not obvious why.  Can you extract a self-contained test case?

			regards, tom lane