Horton

Re: multivariate statistics (v19)

Dilip Kumar <dilipbalaut@gmail.com>

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From: Dilip Kumar <dilipbalaut@gmail.com>
To: Tomas Vondra <tomas.vondra@2ndquadrant.com>
Cc: Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>, Dean Rasheed <dean.a.rasheed@gmail.com>, Heikki Linnakangas <hlinnaka@iki.fi>, Michael Paquier <michael.paquier@gmail.com>, Robert Haas <robertmhaas@gmail.com>, Tatsuo Ishii <ishii@postgresql.org>, David Steele <david@pgmasters.net>, Tom Lane <tgl@sss.pgh.pa.us>, Álvaro Herrera <alvherre@2ndquadrant.com>, Petr Jelinek <petr@2ndquadrant.com>, Jeff Janes <jeff.janes@gmail.com>, "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Date: 2017-01-03T13:42:04Z
Lists: pgsql-hackers 
On Tue, Dec 13, 2016 at 3:20 AM, Tomas Vondra
<tomas.vondra@2ndquadrant.com> wrote:
> attached is v21 of the patch series, rebased to current master (resolving
> the duplicate OID and a few trivial merge conflicts), and also fixing some
> of the issues you reported.

I wanted to test the grouping estimation behaviour with TPCH, While
testing I found some crash so I thought of reporting it.

My setup detail:
TPCH scale factor : 5
Applied all the patch for 21 series, and ran below queries.

postgres=# analyze part;
ANALYZE
postgres=# CREATE STATISTICS s2  WITH (ndistinct) on (p_brand, p_type,
p_size) from part;
CREATE STATISTICS
postgres=# analyze part;
server closed the connection unexpectedly
This probably means the server terminated abnormally
before or while processing the request.
The connection to the server was lost. Attempting reset: Failed.

I think it should be easily reproducible, in case it's not I can send
call stack or core dump.

-- 
Regards,
Dilip Kumar
EnterpriseDB: http://www.enterprisedb.com

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