Movatterモバイル変換

[0]ホーム
URL:

Skip to content

Navigation Menu

Sign in
Appearance settings

Search code, repositories, users, issues, pull requests...

Provide feedback

We read every piece of feedback, and take your input very seriously.

Saved searches

Use saved searches to filter your results more quickly

 Sign up
Appearance settings

Commitff64359

Browse files
committed
Draft
1 parentedf9e2c commitff64359

File tree

2 files changed

+30
-2
lines changed

2 files changed

+30
-2
lines changed

‎src/backend/utils/adt/selfuncs.c

Lines changed: 10 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -3965,6 +3965,7 @@ estimate_multivariate_ndistinct(PlannerInfo *root, RelOptInfo *rel,
39653965
MVNDistinct*stats;
39663966
StatisticExtInfo*matched_info=NULL;
39673967
RangeTblEntry*rte=planner_rt_fetch(rel->relid,root);
3968+
List*statlist;
39683969

39693970
/* bail out immediately if the table has no extended statistics */
39703971
if (!rel->statlist)
@@ -3973,7 +3974,10 @@ estimate_multivariate_ndistinct(PlannerInfo *root, RelOptInfo *rel,
39733974
/* look for the ndistinct statistics object matching the most vars */
39743975
nmatches_vars=0;/* we require at least two matches */
39753976
nmatches_exprs=0;
3976-
foreach(lc,rel->statlist)
3977+
3978+
attempt:
3979+
statlist=list_copy(rel->statlist);
3980+
foreach(lc,statlist)
39773981
{
39783982
ListCell*lc2;
39793983
StatisticExtInfo*info= (StatisticExtInfo*)lfirst(lc);
@@ -4200,7 +4204,11 @@ estimate_multivariate_ndistinct(PlannerInfo *root, RelOptInfo *rel,
42004204
* statistics includes all combinations of attributes.
42014205
*/
42024206
if (!item)
4203-
elog(ERROR,"corrupt MVNDistinct entry");
4207+
{
4208+
statOid=InvalidOid;
4209+
statlist=list_delete_ptr(statlist,matched_info);
4210+
gotoattempt;
4211+
}
42044212

42054213
/* Form the output varinfo list, keeping only unmatched ones */
42064214
foreach(lc,*varinfos)

‎src/test/regress/sql/stats_ext.sql

Lines changed: 20 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -1683,6 +1683,26 @@ SELECT statistics_name, most_common_vals FROM pg_stats_ext x
16831683
SELECT statistics_name, most_common_valsFROM pg_stats_ext_exprs x
16841684
WHERE tablename='stats_ext_tbl'ORDER BY ROW(x.*);
16851685

1686+
CREATETABLEext_linear(xint, yint, zint);
1687+
INSERT INTO ext_linear (x,y,z)SELECT gs%47,gs%71,gs%53
1688+
FROM generate_series(1,100)AS gs;
1689+
CREATE STATISTICS x_y_linearON x,y,zFROM ext_linear
1690+
WITH (method='linear');
1691+
VACUUM ANALYZE ext_linear;
1692+
1693+
-- Statistics built with the 'linear' method don't have x,z combination:
1694+
-- don't complain, but not use this statistic slot.
1695+
SELECT check_estimated_rows('SELECT count(*) FROM ext_linear GROUP BY x,z;');
1696+
-- have statistic combination on (x,y) - get correct estimation.
1697+
SELECT check_estimated_rows('SELECT count(*) FROM ext_linear GROUP BY x,y;');
1698+
CREATE STATISTICS x_y_linear_1ON x,z,yFROM ext_linear WITH (method='linear');
1699+
DROP STATISTICS x_y_linear;
1700+
VACUUM ANALYZE ext_linear;
1701+
-- TODO: Now we have right combination in the second statistic slot and use it
1702+
-- getting correct groups number estimation
1703+
SELECT check_estimated_rows('SELECT count(*) FROM ext_linear GROUP BY x,z;');
1704+
DROPTABLE ext_linear;
1705+
16861706
-- Tidy up
16871707
DROPOPERATOR<<< (int,int);
16881708
DROPFUNCTION op_leak(int,int);

0 commit comments

Comments
 (0)
[8]ページ先頭
©2009-2025 Movatter.jp