Horton

Re: WIP: multivariate statistics / proof of concept

Tomas Vondra <tomas.vondra@2ndquadrant.com>

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From: Tomas Vondra <tomas.vondra@2ndquadrant.com>
To: Kyotaro HORIGUCHI <horiguchi.kyotaro@lab.ntt.co.jp>
Cc: pgsql-hackers@postgresql.org
Date: 2015-03-24T10:24:21Z
Lists: pgsql-hackers 
Hello,

On 03/24/15 06:34, Kyotaro HORIGUCHI wrote:
>
> Sorry, not shown above, the *previous* t1 had been done "alter table
> t1 add statistics (a, b, c)". Removing t1 didn't remove the setting.
> reiniting cluster let me do that without error.

OK, thanks. My guess is this issue got already fixed in my working copy, 
but I will double-check that.

Admittedly, the management of the stats (e.g. removing stats when the 
table is dropped) is one of the incomplete parts. You have to delete the 
rows manually from pg_mv_statistic.

-- 
--
Tomas Vondra                   http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services

Commits

  1. Collect and use multi-column dependency stats

  2. Implement SortSupport for macaddr data type

  3. Implement multivariate n-distinct coefficients

  4. Generate fmgr prototypes automatically