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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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5
src/include/statistics/extended_stats_internal.h
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@@ -52,6 +52,11 @@ extern MVNDistinct *statext_ndistinct_build(double totalrows,
extern bytea *statext_ndistinct_serialize(MVNDistinct *ndistinct);
extern MVNDistinct *statext_ndistinct_deserialize(bytea *data);
extern MVDependencies *statext_dependencies_build(int numrows, HeapTuple *rows,
Bitmapset *attrs, VacAttrStats **stats);
extern bytea *statext_dependencies_serialize(MVDependencies *dependencies);
extern MVDependencies *statext_dependencies_deserialize(bytea *data);
extern MultiSortSupport multi_sort_init(int ndims);
extern void multi_sort_add_dimension(MultiSortSupport mss, int sortdim,
Oid oper);