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Date: Wed, 5 Jan 2011 12:06:41 -0800 (PST)
From: Marc Antonio <marc.queiroz@gmail.com>
To: pgsql-performance@postgresql.org
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Subject: Re: Major performance problem after upgrade from 8.3 to 8.4
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Hi,

I had a similar problem with many left join, reading about planning
optimization i tried to edit postgresql.conf and uncommented the line
join_collapse_limit = 8 and set it to 1, disables collapsing of explicit .
My query its taking 2000s in 8.4 and the same query 2ms in 8.3. Now its
working fast in 8.4.

Best regards,

Marc
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