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To: Sean Chittenden <sean@chittenden.org>
Cc: Bruno Wolff III <bruno@wolff.to>,
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Subject: Re: bad estimates
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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