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From: Tom Lane <tgl@sss.pgh.pa.us>
To: =?KOI8-U?B?96bUwcymyiD0yc3eydvJzg==?= <tivv00@gmail.com>
cc: pgsql-performance@postgresql.org
Subject: Re: correlated exists with join is slow.
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Comments: In-reply-to =?KOI8-U?B?96bUwcymyiD0yc3eydvJzg==?= <tivv00@gmail.com>
	message dated "Mon, 18 Jun 2012 16:47:42 +0300"
Date: Mon, 18 Jun 2012 10:52:35 -0400
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=?KOI8-U?B?96bUwcymyiD0yc3eydvJzg==?= <tivv00@gmail.com> writes:
> Today I've found a query that I thought will be fast turned out to be slow.
> The problem is correlated exists with join - it does not want to make
> correlated nested loop to make exists check.

9.2 will make this all better.  These are exactly the type of case where
you need the "parameterized path" stuff.

			regards, tom lane