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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andrzej Zawadzki <zawadaa@wp.pl>
cc: pgsql-performance@postgresql.org
Subject: Re: Strange behavior after upgrade from 9.0 to 9.2
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Comments: In-reply-to Andrzej Zawadzki <zawadaa@wp.pl>
	message dated "Mon, 08 Oct 2012 17:41:17 +0200"
Date: Mon, 08 Oct 2012 11:56:27 -0400
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Andrzej Zawadzki <zawadaa@wp.pl> writes:
> On 08.10.2012 16:52, Tom Lane wrote:
>> [ counts... ]  You've got nine base relations in that query.  I think
>> you need to increase from_collapse_limit and/or join_collapse_limit.

> Bingo! Thank you!

> But... looks like in 9.0 this worked differently or option was skipped?
> Because I had default settings of that options and query has worked fine.

It looks like 9.0 wasn't flattening the EXISTS subqueries, so those
tables didn't count as relations of the main query.

			regards, tom lane