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From: Ken Geis <kgeis@speakeasy.org>
To: Sean Chittenden <sean@chittenden.org>
Cc: Bruno Wolff III <bruno@wolff.to>
Cc: pgsql-performance@postgresql.org
Subject: Re: bad estimates
Date: Fri, 29 Aug 2003 09:56:59 -0700
Message-ID: <3F4F85DB.2030402@speakeasy.org> (raw)
In-Reply-To: <20030829163613.GA51475@perrin.nxad.com>
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	<20030829033818.GA5577@wolff.to>
	<3F4ECC78.7090502@speakeasy.org>
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	<3F4F7A07.30404@speakeasy.org>
	<20030829163613.GA51475@perrin.nxad.com>

Sean Chittenden wrote:
>>I found I'm suffering from an effect detailed in a previous thread titled
>>
>>	Does "correlation" mislead the optimizer on large tables?
> 
> 
> I don't know about large tables, but this is a big problem and
> something I'm going to spend some time validating later today.  I
> think Manfred's patch is pretty good and certainly better than where
> we are but I haven't used it yet to see if it's the magic ticket for
> many of these index problems.

I had to dig through a lot of archives to find this.  Is this the patch, 
from last October?

http://members.aon.at/pivot/pg/16-correlation.diff

If so, I'll try it out and report my results.


Ken

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