Horton

Re: [HACKERS] PATCH: multivariate histograms and MCV lists

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

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From: Tomas Vondra <tomas.vondra@2ndquadrant.com>
To: Dean Rasheed <dean.a.rasheed@gmail.com>
Cc: David Rowley <david.rowley@2ndquadrant.com>, Alvaro Herrera <alvherre@2ndquadrant.com>, Michael Paquier <michael@paquier.xyz>, Andres Freund <andres@anarazel.de>, Thomas Munro <thomas.munro@enterprisedb.com>, Bruce Momjian <bruce@momjian.us>, Mark Dilger <hornschnorter@gmail.com>, Pg Hackers <pgsql-hackers@postgresql.org>
Date: 2019-03-13T01:25:40Z
Lists: pgsql-hackers

Attachments

Hi,

attached is an updated version of the patch, addressing most of the
issues raised in the recent reviews. There are two main exceptions:

1) I haven't reworked the regression tests to use a function to check
cardinality estimates and making them faster.

2) Review handling of bitmap in statext_is_compatible_clause_internal
when processing AND/OR/NOT clauses.

I plan to look into those items next, but I don't want block review of
other parts of the patch unnecessarily.


regards

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

Commits

  1. Convert pre-existing stats_ext tests to new style

  2. Add support for multivariate MCV lists

  3. Improve ANALYZE's strategy for finding MCVs.

  4. Clone extended stats in CREATE TABLE (LIKE INCLUDING ALL)

  5. Try again to fix accumulation of parallel worker instrumentation.

  6. Adjust psql \d query to avoid use of @> operator.

  7. Message style fixes

  8. Add security checks to selectivity estimation functions