From 4e690419874eb128bb3371f9c39ed95d8e731f64 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?=C3=81lvaro=20Herrera?= Date: Fri, 17 Oct 2025 13:55:15 +0200 Subject: [PATCH v4] Restructure CreateStatsStmt parse-analysis processing Previously, a lot of code would be run in the ProcessUtility pipeline, where it is not welcome (that's supposed to be just a giant dispatcher switch). Move the parse analysis code to CreateStatistics() instead, which then means we don't need to open the relation twice; it also allows us to give a better error message when something other than a relation name is given in the FROM clause. It also means we no longer need to do the transform step in ATPostAlterTypeParse(), which saves a bit of code. Author: Jian He Discussion: https://postgr.es/m/CACJufxFcvo=fM6J9RC88n1U=eS9+5QdftwUNQMu5h7OgjmqDwQ@mail.gmail.com --- src/backend/commands/statscmds.c | 13 +++++++++++-- src/backend/commands/tablecmds.c | 16 +--------------- src/backend/parser/parse_utilcmd.c | 13 +++---------- src/backend/tcop/utility.c | 29 +---------------------------- src/include/commands/defrem.h | 2 +- src/include/parser/parse_utilcmd.h | 2 +- 6 files changed, 18 insertions(+), 57 deletions(-) diff --git a/src/backend/commands/statscmds.c b/src/backend/commands/statscmds.c index 27bf67e7c4b..632228c13ed 100644 --- a/src/backend/commands/statscmds.c +++ b/src/backend/commands/statscmds.c @@ -30,6 +30,7 @@ #include "miscadmin.h" #include "nodes/nodeFuncs.h" #include "optimizer/optimizer.h" +#include "parser/parse_utilcmd.h" #include "statistics/statistics.h" #include "utils/acl.h" #include "utils/builtins.h" @@ -58,9 +59,14 @@ compare_int16(const void *a, const void *b) /* * CREATE STATISTICS + * + * queryString is the source text of the CREATE STATISTICS command, if any. + * + * Normally stmt has not already undergone transformation, but in some cases + * it might have, such as CREATE TABLE (LIKE). */ ObjectAddress -CreateStatistics(CreateStatsStmt *stmt) +CreateStatistics(CreateStatsStmt *stmt, const char *queryString) { int16 attnums[STATS_MAX_DIMENSIONS]; int nattnums = 0; @@ -113,7 +119,7 @@ CreateStatistics(CreateStatsStmt *stmt) if (!IsA(rln, RangeVar)) ereport(ERROR, (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("only a single relation is allowed in CREATE STATISTICS"))); + errmsg("CREATE STATISTICS only supports relation names in the FROM clause"))); /* * CREATE STATISTICS will influence future execution plans but does @@ -151,6 +157,9 @@ CreateStatistics(CreateStatsStmt *stmt) Assert(rel); relid = RelationGetRelid(rel); + /* Run parse analysis */ + stmt = transformStatsStmt(rel, stmt, queryString); + /* * If the node has a name, split it up and determine creation namespace. * If not, put the object in the same namespace as the relation, and cons diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index 5fd8b51312c..a1732b71e55 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -9650,16 +9650,7 @@ static ObjectAddress ATExecAddStatistics(AlteredTableInfo *tab, Relation rel, CreateStatsStmt *stmt, bool is_rebuild, LOCKMODE lockmode) { - ObjectAddress address; - - Assert(IsA(stmt, CreateStatsStmt)); - - /* The CreateStatsStmt has already been through transformStatsStmt */ - Assert(stmt->transformed); - - address = CreateStatistics(stmt); - - return address; + return CreateStatistics(stmt, NULL); } /* @@ -15632,11 +15623,6 @@ ATPostAlterTypeParse(Oid oldId, Oid oldRelId, Oid refRelId, char *cmd, querytree_list = lappend(querytree_list, stmt); querytree_list = list_concat(querytree_list, afterStmts); } - else if (IsA(stmt, CreateStatsStmt)) - querytree_list = lappend(querytree_list, - transformStatsStmt(oldRelId, - (CreateStatsStmt *) stmt, - cmd)); else querytree_list = lappend(querytree_list, stmt); } diff --git a/src/backend/parser/parse_utilcmd.c b/src/backend/parser/parse_utilcmd.c index e96b38a59d5..89c8315117b 100644 --- a/src/backend/parser/parse_utilcmd.c +++ b/src/backend/parser/parse_utilcmd.c @@ -3137,16 +3137,14 @@ transformIndexStmt(Oid relid, IndexStmt *stmt, const char *queryString) * transformStatsStmt - parse analysis for CREATE STATISTICS * * To avoid race conditions, it's important that this function relies only on - * the passed-in relid (and not on stmt->relation) to determine the target - * relation. + * the passed-in rel (and not on stmt->relation) as the target relation. */ CreateStatsStmt * -transformStatsStmt(Oid relid, CreateStatsStmt *stmt, const char *queryString) +transformStatsStmt(Relation rel, CreateStatsStmt *stmt, const char *queryString) { ParseState *pstate; ParseNamespaceItem *nsitem; ListCell *l; - Relation rel; /* Nothing to do if statement already transformed. */ if (stmt->transformed) @@ -3158,10 +3156,8 @@ transformStatsStmt(Oid relid, CreateStatsStmt *stmt, const char *queryString) /* * Put the parent table into the rtable so that the expressions can refer - * to its fields without qualification. Caller is responsible for locking - * relation, but we still need to open it. + * to its fields without qualification. */ - rel = relation_open(relid, NoLock); nsitem = addRangeTableEntryForRelation(pstate, rel, AccessShareLock, NULL, false, true); @@ -3196,9 +3192,6 @@ transformStatsStmt(Oid relid, CreateStatsStmt *stmt, const char *queryString) free_parsestate(pstate); - /* Close relation */ - table_close(rel, NoLock); - /* Mark statement as successfully transformed */ stmt->transformed = true; diff --git a/src/backend/tcop/utility.c b/src/backend/tcop/utility.c index 918db53dd5e..027356f6e77 100644 --- a/src/backend/tcop/utility.c +++ b/src/backend/tcop/utility.c @@ -1866,34 +1866,7 @@ ProcessUtilitySlow(ParseState *pstate, break; case T_CreateStatsStmt: - { - Oid relid; - CreateStatsStmt *stmt = (CreateStatsStmt *) parsetree; - RangeVar *rel = (RangeVar *) linitial(stmt->relations); - - if (!IsA(rel, RangeVar)) - ereport(ERROR, - (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("CREATE STATISTICS only supports relation names in the FROM clause"))); - - /* - * CREATE STATISTICS will influence future execution plans - * but does not interfere with currently executing plans. - * So it should be enough to take ShareUpdateExclusiveLock - * on relation, conflicting with ANALYZE and other DDL - * that sets statistical information, but not with normal - * queries. - * - * XXX RangeVarCallbackOwnsRelation not needed here, to - * keep the same behavior as before. - */ - relid = RangeVarGetRelid(rel, ShareUpdateExclusiveLock, false); - - /* Run parse analysis ... */ - stmt = transformStatsStmt(relid, stmt, queryString); - - address = CreateStatistics(stmt); - } + address = CreateStatistics((CreateStatsStmt *) parsetree, queryString); break; case T_AlterStatsStmt: diff --git a/src/include/commands/defrem.h b/src/include/commands/defrem.h index dd22b5efdfd..684f62109fd 100644 --- a/src/include/commands/defrem.h +++ b/src/include/commands/defrem.h @@ -85,7 +85,7 @@ extern void RemoveOperatorById(Oid operOid); extern ObjectAddress AlterOperator(AlterOperatorStmt *stmt); /* commands/statscmds.c */ -extern ObjectAddress CreateStatistics(CreateStatsStmt *stmt); +extern ObjectAddress CreateStatistics(CreateStatsStmt *stmt, const char *queryString); extern ObjectAddress AlterStatistics(AlterStatsStmt *stmt); extern void RemoveStatisticsById(Oid statsOid); extern void RemoveStatisticsDataById(Oid statsOid, bool inh); diff --git a/src/include/parser/parse_utilcmd.h b/src/include/parser/parse_utilcmd.h index 4965fac4495..67255799f0a 100644 --- a/src/include/parser/parse_utilcmd.h +++ b/src/include/parser/parse_utilcmd.h @@ -26,7 +26,7 @@ extern AlterTableStmt *transformAlterTableStmt(Oid relid, AlterTableStmt *stmt, List **afterStmts); extern IndexStmt *transformIndexStmt(Oid relid, IndexStmt *stmt, const char *queryString); -extern CreateStatsStmt *transformStatsStmt(Oid relid, CreateStatsStmt *stmt, +extern CreateStatsStmt *transformStatsStmt(Relation rel, CreateStatsStmt *stmt, const char *queryString); extern void transformRuleStmt(RuleStmt *stmt, const char *queryString, List **actions, Node **whereClause); -- 2.47.3