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Re: left join performance problem

From: Bruno Wolff III <bruno(at)wolff(dot)to>
To: "Jim C(dot) Nasby" <jim(at)nasby(dot)net>
Cc: pgsql-performance(at)postgresql(dot)org
Subject: Re: left join performance problem
Date: 2003-06-16 08:07:18
Message-ID: 20030616080718.GB25847@wolff.to (view raw or flat)
Thread:
Lists: pgsql-performance
On Mon, Jun 16, 2003 at 00:36:29 -0500,
  "Jim C. Nasby" <jim(at)nasby(dot)net> wrote:
> On Mon, Jun 16, 2003 at 01:28:26AM -0400, Tom Lane wrote:
> > "Jim C. Nasby" <jim(at)nasby(dot)net> writes:
> > > Any chance of getting a TODO added that would provide the option of
> > > having the optimizer pick join order when you're using the ANSI join
> > > syntax?
> > 
> > No ... because it's already DONE.
>  
> DOH, I forgot about the subselect trick. Nevermind.

In 7.4 there is a GUC setting to control this. I believe the default
is to not constrain the join order any more than is necessary to
preserve semantics.

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