hcq/postgresql
1
0
Fork 0
mirror of https://git.postgresql.org/git/postgresql.git synced 2026-02-10 05:57:46 +08:00
Code Issues Packages Projects Releases Wiki Activity

Add stxdinherit flag to pg_statistic_ext_data

Browse Source 
Add pg_statistic_ext_data.stxdinherit flag, so that for each extended
statistics definition we can store two versions of data - one for the
relation alone, one for the whole inheritance tree. This is analogous to
pg_statistic.stainherit, but we failed to include such flag in catalogs
for extended statistics, and we had to work around it (see commits
859b3003de, 36c4bc6e72 and 20b9fa308e).

This changes the relationship between the two catalogs storing extended
statistics objects (pg_statistic_ext and pg_statistic_ext_data). Until
now, there was a simple 1:1 mapping - for each definition there was one
pg_statistic_ext_data row, and this row was inserted while creating the
statistics (and then updated during ANALYZE). With the stxdinherit flag,
we don't know how many rows there will be (child relations may be added
after the statistics object is defined), so there may be up to two rows.

We could make CREATE STATISTICS to always create both rows, but that
seems wasteful - without partitioning we only need stxdinherit=false
rows, and declaratively partitioned tables need only stxdinherit=true.
So we no longer initialize pg_statistic_ext_data in CREATE STATISTICS,
and instead make that a responsibility of ANALYZE. Which is what we do
for regular statistics too.

Patch by me, with extensive improvements and fixes by Justin Pryzby.

Author: Tomas Vondra, Justin Pryzby
Reviewed-by: Tomas Vondra, Justin Pryzby
Discussion: https://postgr.es/m/20210923212624.GI831%40telsasoft.com
This commit is contained in:
Tomas Vondra
2022-01-16 13:37:56 +01:00
parent e701bdd2f0
commit 269b532aef
19 changed files with 251 additions and 236 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
src/include/catalog/catversion.h
View File

@ -53,6 +53,6 @@
*/
/* yyyymmddN */
#define CATALOG_VERSION_NO 202201121
#define CATALOG_VERSION_NO 202201161
#endif

4
src/include/catalog/pg_statistic_ext_data.h
View File

@ -32,6 +32,7 @@ CATALOG(pg_statistic_ext_data,3429,StatisticExtDataRelationId)
{
Oid stxoid BKI_LOOKUP(pg_statistic_ext); /* statistics object
* this data is for */
bool stxdinherit; /* true if inheritance children are included */
#ifdef CATALOG_VARLEN /* variable-length fields start here */
@ -53,6 +54,7 @@ typedef FormData_pg_statistic_ext_data * Form_pg_statistic_ext_data;
DECLARE_TOAST(pg_statistic_ext_data, 3430, 3431);
DECLARE_UNIQUE_INDEX_PKEY(pg_statistic_ext_data_stxoid_index, 3433, StatisticExtDataStxoidIndexId, on pg_statistic_ext_data using btree(stxoid oid_ops));
DECLARE_UNIQUE_INDEX_PKEY(pg_statistic_ext_data_stxoid_inh_index, 3433, StatisticExtDataStxoidInhIndexId, on pg_statistic_ext_data using btree(stxoid oid_ops, stxdinherit bool_ops));
#endif /* PG_STATISTIC_EXT_DATA_H */

1
src/include/commands/defrem.h
View File

@ -83,6 +83,7 @@ extern ObjectAddress AlterOperator(AlterOperatorStmt *stmt);
extern ObjectAddress CreateStatistics(CreateStatsStmt *stmt);
extern ObjectAddress AlterStatistics(AlterStatsStmt *stmt);
extern void RemoveStatisticsById(Oid statsOid);
extern void RemoveStatisticsDataById(Oid statsOid, bool inh);
extern Oid StatisticsGetRelation(Oid statId, bool missing_ok);
/* commands/aggregatecmds.c */

1
src/include/nodes/pathnodes.h
View File

@ -934,6 +934,7 @@ typedef struct StatisticExtInfo
NodeTag type;
Oid statOid; /* OID of the statistics row */
bool inherit; /* includes child relations */
RelOptInfo *rel; /* back-link to statistic's table */
char kind; /* statistics kind of this entry */
Bitmapset *keys; /* attnums of the columns covered */

11
src/include/statistics/statistics.h
View File

@ -94,11 +94,11 @@ typedef struct MCVList
MCVItem items[FLEXIBLE_ARRAY_MEMBER]; /* array of MCV items */
} MCVList;
extern MVNDistinct *statext_ndistinct_load(Oid mvoid);
extern MVDependencies *statext_dependencies_load(Oid mvoid);
extern MCVList *statext_mcv_load(Oid mvoid);
extern MVNDistinct *statext_ndistinct_load(Oid mvoid, bool inh);
extern MVDependencies *statext_dependencies_load(Oid mvoid, bool inh);
extern MCVList *statext_mcv_load(Oid mvoid, bool inh);
extern void BuildRelationExtStatistics(Relation onerel, double totalrows,
extern void BuildRelationExtStatistics(Relation onerel, bool inh, double totalrows,
int numrows, HeapTuple *rows,
int natts, VacAttrStats **vacattrstats);
extern int ComputeExtStatisticsRows(Relation onerel,
@ -121,9 +121,10 @@ extern Selectivity statext_clauselist_selectivity(PlannerInfo *root,
bool is_or);
extern bool has_stats_of_kind(List *stats, char requiredkind);
extern StatisticExtInfo *choose_best_statistics(List *stats, char requiredkind,
bool inh,
Bitmapset **clause_attnums,
List **clause_exprs,
int nclauses);
extern HeapTuple statext_expressions_load(Oid stxoid, int idx);
extern HeapTuple statext_expressions_load(Oid stxoid, bool inh, int idx);
#endif /* STATISTICS_H */