Re: multivariate statistics v8

From: Bruce Momjian <bruce(at)momjian(dot)us>
To: Robert Haas <robertmhaas(at)gmail(dot)com>
Cc: Tomas Vondra <tomas(dot)vondra(at)2ndquadrant(dot)com>, "pgsql-hackers(at)postgresql(dot)org" <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: multivariate statistics v8
Date: 2016-01-20 21:37:43
Message-ID: 20160120213743.GA9092@momjian.us
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On Wed, Jan 20, 2016 at 02:20:38PM -0500, Robert Haas wrote:
> On Wed, Dec 23, 2015 at 2:07 PM, Tomas Vondra
> <tomas(dot)vondra(at)2ndquadrant(dot)com> wrote:
> > The remaining question is how unique the statistics name should be.
> > My initial plan was to make it unique within a table, but that of
> > course does not work well with the DROP STATISTICS (it'd have to
> > specify the table name also), and it'd also now work with statistics
> > on multiple tables (which is one of the reasons for abandoning ALTER
> > TABLE stuff).
> >
> > So I think it should be unique across tables. Statistics are hardly
> > a global object, so it should be unique within a schema. I thought
> > that simply using the schema of the table would work, but that of
> > course breaks with multiple tables in different schemas. So the only
> > solution seems to be explicit schema for statistics.
>
> That solution seems good to me.
>
> (with apologies for not having looked at the rest of this much at all)

Woh, this will be an optimizer game-changer, from the user perspective!

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Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://enterprisedb.com

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