Message-ID: <5226D7FF.7020000@usit.uio.no>
Date: Wed, 04 Sep 2013 08:49:35 +0200
From: Rafael Martinez <r.m.guerrero@usit.uio.no>
Organization: University of Oslo
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To: Tom Lane <tgl@sss.pgh.pa.us>
CC: pgsql-performance@postgresql.org
Subject: Re: SQL statement over 500% slower with 9.2 compared with
 9.1
References: <521B4B2A.5010800@usit.uio.no> <17619.1377716890@sss.pgh.pa.us>
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On 08/28/2013 09:08 PM, Tom Lane wrote:
[..........]

> 
> If you don't want to do any major rewriting, you could probably
> stick an OFFSET 0 into the outer EXISTS sub-select (and/or the
> inner one) to get something similar to the 9.1 plan.
> 

Thank you for your help.

Using OFFSET 0 in

SELECT  *
FROM    FilmParticipation C
WHERE   C.partType = 'cast'
AND C.filmId = D.filmId
AND C.personId = D.personId
OFFSET 0

give us a result similar to 9.1.

This SQL is used as an example in one of the database courses at the
University. I will send them this information and they can decide if
they want to rewrite the statement or use the OFFSET trick.

regards,
- -- 
 Rafael Martinez Guerrero
 Center for Information Technology
 University of Oslo, Norway

 PGP Public Key: http://folk.uio.no/rafael/
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