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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Merlin Moncure <mmoncure@gmail.com>
cc: Rodrigo Rosenfeld Rosas <rr.rosas@gmail.com>,
	pgsql-performance@postgresql.org
Subject: Re: Query completed in < 1s in PG 9.1 and ~ 700s in PG 9.2
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Comments: In-reply-to Merlin Moncure <mmoncure@gmail.com>
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Merlin Moncure <mmoncure@gmail.com> writes:
> Problem could also be no statistics (run ANALYZE to test) or some
> other configuration problem (like index locale), or a bona fide
> regression.

I'm wondering about join_collapse_limit in particular --- if that wasn't
cranked up in the 9.1 installation, it would be pure luck if you got a
good query plan for an example like this.  Maybe that and/or other
parameter settings didn't get transposed to the 9.2 installation.

			regards, tom lane