Re: bad estimates

> >>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.

Same guy, but that patch is pretty out of date and has been replaced
by some newer work that's much better.

From: Manfred Koizar <mkoi-pg@aon.at>
Cc: pgsql-hackers@postgresql.org
Subject: Re: [HACKERS] Correlation in cost_index()
Date: Wed, 20 Aug 2003 19:57:12 +0200
Message-ID: <lo97kvkmjatb0ain1e7ad69ccslripcafv@4ax.com>


and


From: Manfred Koizar <mkoi-pg@aon.at>
To: pgsql-hackers@postgresql.org
Subject: [HACKERS] Again on index correlation
Date: Wed, 20 Aug 2003 21:21:14 +0200
Message-ID: <dhd7kvs4niqijnerr9mi38oeih1o7j2s28@4ax.com>


-sc

--
Sean Chittenden