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From: Craig Ringer <ringerc@ringerc.id.au>
To: Ioannis Anagnostopoulos <ioannis@anatec.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: A very long running query....
Date: Sat, 21 Jul 2012 16:02:21 +0800
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On 07/21/2012 06:19 AM, Ioannis Anagnostopoulos wrote:

> On this Ubuntu installation the default_statistics_target = 1000 and 
> not 100. Do you think that this might be an issue?

Nope. You should generally avoid setting default_statistics_target too 
high anyway; leave it where it is and use ALTER TABLE ... ALTER COLUMN 
... SET STATISTICS to raise the targets on columns where you're seeing 
bad statistics estimates.

http://www.postgresql.org/docs/9.1/static/sql-altertable.html

Also make sure autovaccum is running frequently so it keeps the stats up 
to date.

--
Craig Ringer

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