Date: Tue, 22 Sep 2015 22:55:54 -0300
From: Alvaro Herrera <alvherre@2ndquadrant.com>
To: Peter Geoghegan <pg@heroku.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Jim Nasby <Jim.Nasby@bluetreble.com>,
 Pg Hackers <pgsql-hackers@postgresql.org>
Subject: Re: Less than ideal error reporting in pg_stat_statements
Message-ID: <20150923015554.GM295765@alvherre.pgsql>
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Peter Geoghegan wrote:

> My guess is that this very large query involved a very large number of
> constants, possibly contained inside an " IN ( )". Slight variants of
> the same query, that a human would probably consider to be equivalent
> have caused artificial pressure on garbage collection.

So if I have multiple queries like

SELECT foo FROM bar WHERE baz IN (a, b)
SELECT foo FROM bar WHERE baz IN (a, b, c)

they are not normalized down to the same?  That seems odd.

-- 
Álvaro Herrera                http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services


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