From: Shaun Thomas <sthomas@optionshouse.com>
To: Heikki Linnakangas <hlinnakangas@vmware.com>
Cc: pgsql-performance@postgresql.org <pgsql-performance@postgresql.org>
Subject: Re: Thinking About Correlated Columns (again)
Date: Wed, 15 May 2013 11:27:29 -0500
Message-ID: <5193B771.70502@optionshouse.com> (raw)
In-Reply-To: <5193AF36.3040409@vmware.com>
References: <5193AA62.2040700@optionshouse.com>
<5193AF36.3040409@vmware.com>
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On 05/15/2013 10:52 AM, Heikki Linnakangas wrote:
> I think it would be pretty straightforward to use such a statistic,
> once we have it. So perhaps we should get started by allowing the DBA
> to set a correlation metric manually, and use that in the planner.
The planner already kinda does this with functional indexes. It would
definitely be nice to override the stats with known correlations when
possible.
--
Shaun Thomas
OptionsHouse | 141 W. Jackson Blvd. | Suite 500 | Chicago IL, 60604
312-676-8870
sthomas@optionshouse.com
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To: pgsql-performance@postgresql.org
Cc: sthomas@optionshouse.com, hlinnakangas@vmware.com
Subject: Re: Thinking About Correlated Columns (again)
In-Reply-To: <5193B771.70502@optionshouse.com>
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