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Collect and use multi-column dependency stats

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Follow on patch in the multi-variate statistics patch series.

CREATE STATISTICS s1 WITH (dependencies) ON (a, b) FROM t;
ANALYZE;
will collect dependency stats on (a, b) and then use the measured
dependency in subsequent query planning.

Commit 7b504eb282 added
CREATE STATISTICS with n-distinct coefficients. These are now
specified using the mutually exclusive option WITH (ndistinct).

Author: Tomas Vondra, David Rowley
Reviewed-by: Kyotaro HORIGUCHI, Álvaro Herrera, Dean Rasheed, Robert Haas
and many other comments and contributions
Discussion: https://postgr.es/m/56f40b20-c464-fad2-ff39-06b668fac47c@2ndquadrant.com
This commit is contained in:
Simon Riggs
2017-04-05 18:00:42 -04:00
parent 00b6b6feb1
commit 2686ee1b7c
31 changed files with 2035 additions and 79 deletions
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1
contrib/file_fdw/file_fdw.c
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@ -1013,6 +1013,7 @@ estimate_size(PlannerInfo *root, RelOptInfo *baserel,
baserel->baserestrictinfo,
0,
JOIN_INNER,
NULL,
NULL);
nrows = clamp_row_est(nrows);