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Date: Tue, 12 Jul 2005 09:35:52 -0500
From: Bruno Wolff III <bruno@wolff.to>
To: Dario Pudlo <dariop@unitech.com.ar>
Cc: pgsql-performance@postgresql.org
Subject: Re: join and query planner
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	Dario Pudlo <dariop@unitech.com.ar>, pgsql-performance@postgresql.org
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On Wed, Jul 06, 2005 at 18:54:02 -0300,
  Dario Pudlo <dariop@unitech.com.ar> wrote:
> (first at all, sorry for my english)
> Hi.
>    - Does "left join" restrict the order in which the planner must join
> tables? I've read about join, but i'm not sure about left join...

The left join operator is not associative so in general the planner doesn't
have much flexibility to reorder left (or right) joins.