misleading error message in ProcessUtilitySlow T_CreateStatsStmt

From bebffcaa22a047c61b0fa588db56db60e59dc9ef Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C3=81lvaro=20Herrera?= <alvherre@kurilemu.de>
Date: Thu, 28 Aug 2025 19:49:14 +0200
Subject: [PATCH] rewrite ProcessUtilitySlow code for CreateStatsStmt

---
 src/backend/commands/statscmds.c   | 26 +++++-----------
 src/backend/commands/tablecmds.c   |  4 +--
 src/backend/parser/parse_utilcmd.c | 13 +++++---
 src/backend/tcop/utility.c         | 48 +++++++++++++++++-------------
 src/include/commands/defrem.h      |  2 +-
 src/include/parser/parse_utilcmd.h |  2 +-
 6 files changed, 49 insertions(+), 46 deletions(-)

diff --git a/src/backend/commands/statscmds.c b/src/backend/commands/statscmds.c
index e24d540cd45..07b2b5bfef3 100644
--- a/src/backend/commands/statscmds.c
+++ b/src/backend/commands/statscmds.c
@@ -59,7 +59,7 @@ compare_int16(const void *a, const void *b)
  *		CREATE STATISTICS
  */
 ObjectAddress
-CreateStatistics(CreateStatsStmt *stmt)
+CreateStatistics(CreateStatsStmt *stmt, List *relids)
 {
 	int16		attnums[STATS_MAX_DIMENSIONS];
 	int			nattnums = 0;
@@ -92,28 +92,18 @@ CreateStatistics(CreateStatsStmt *stmt)
 	ListCell   *cell;
 	ListCell   *cell2;
 
-	Assert(IsA(stmt, CreateStatsStmt));
-
 	/*
 	 * Examine the FROM clause.  Currently, we only allow it to be a single
 	 * simple table, but later we'll probably allow multiple tables and JOIN
-	 * syntax.  The grammar is already prepared for that, so we have to check
-	 * here that what we got is what we can support.
+	 * syntax.  Parse analysis checked the list length already, so this is
+	 * just defense-in-depth.
 	 */
-	if (list_length(stmt->relations) != 1)
-		ereport(ERROR,
-				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-				 errmsg("only a single relation is allowed in CREATE STATISTICS")));
+	Assert(list_length(stmt->relations) == list_length(relids));
+	if (list_length(relids) != 1)
+		elog(ERROR, "only a single relation is allowed in CREATE STATISTICS");
 
-	foreach(cell, stmt->relations)
+	foreach_oid(relid, relids)
 	{
-		Node	   *rln = (Node *) lfirst(cell);
-
-		if (!IsA(rln, RangeVar))
-			ereport(ERROR,
-					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-					 errmsg("only a single relation is allowed in CREATE STATISTICS")));
-
 		/*
 		 * CREATE STATISTICS will influence future execution plans but does
 		 * not interfere with currently executing plans.  So it should be
@@ -121,7 +111,7 @@ CreateStatistics(CreateStatsStmt *stmt)
 		 * conflicting with ANALYZE and other DDL that sets statistical
 		 * information, but not with normal queries.
 		 */
-		rel = relation_openrv((RangeVar *) rln, ShareUpdateExclusiveLock);
+		rel = relation_open(relid, ShareUpdateExclusiveLock);
 
 		/* Restrict to allowed relation types */
 		if (rel->rd_rel->relkind != RELKIND_RELATION &&
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index 082a3575d62..1779bae80cb 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -9654,7 +9654,7 @@ ATExecAddStatistics(AlteredTableInfo *tab, Relation rel,
 	/* The CreateStatsStmt has already been through transformStatsStmt */
 	Assert(stmt->transformed);
 
-	address = CreateStatistics(stmt);
+	address = CreateStatistics(stmt, list_make1_oid(RelationGetRelid(rel)));
 
 	return address;
 }
@@ -15631,7 +15631,7 @@ ATPostAlterTypeParse(Oid oldId, Oid oldRelId, Oid refRelId, char *cmd,
 		}
 		else if (IsA(stmt, CreateStatsStmt))
 			querytree_list = lappend(querytree_list,
-									 transformStatsStmt(oldRelId,
+									 transformStatsStmt(list_make1_oid(oldRelId),
 														(CreateStatsStmt *) stmt,
 														cmd));
 		else
diff --git a/src/backend/parser/parse_utilcmd.c b/src/backend/parser/parse_utilcmd.c
index afcf54169c3..587e2ef439c 100644
--- a/src/backend/parser/parse_utilcmd.c
+++ b/src/backend/parser/parse_utilcmd.c
@@ -3138,11 +3138,11 @@ 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 relids list (and not on stmt->relations) to determine the
+ * target relation.
  */
 CreateStatsStmt *
-transformStatsStmt(Oid relid, CreateStatsStmt *stmt, const char *queryString)
+transformStatsStmt(List *relids, CreateStatsStmt *stmt, const char *queryString)
 {
 	ParseState *pstate;
 	ParseNamespaceItem *nsitem;
@@ -3153,6 +3153,11 @@ transformStatsStmt(Oid relid, CreateStatsStmt *stmt, const char *queryString)
 	if (stmt->transformed)
 		return stmt;
 
+	if (list_length(relids) != 1)
+		ereport(ERROR,
+				errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+				errmsg("only a single relation is allowed in CREATE STATISTICS"));
+
 	/* Set up pstate */
 	pstate = make_parsestate(NULL);
 	pstate->p_sourcetext = queryString;
@@ -3162,7 +3167,7 @@ transformStatsStmt(Oid relid, CreateStatsStmt *stmt, const char *queryString)
 	 * to its fields without qualification.  Caller is responsible for locking
 	 * relation, but we still need to open it.
 	 */
-	rel = relation_open(relid, NoLock);
+	rel = relation_open(linitial_oid(relids), NoLock);
 	nsitem = addRangeTableEntryForRelation(pstate, rel,
 										   AccessShareLock,
 										   NULL, false, true);
diff --git a/src/backend/tcop/utility.c b/src/backend/tcop/utility.c
index 4f4191b0ea6..e09da051310 100644
--- a/src/backend/tcop/utility.c
+++ b/src/backend/tcop/utility.c
@@ -1867,32 +1867,40 @@ ProcessUtilitySlow(ParseState *pstate,
 
 			case T_CreateStatsStmt:
 				{
-					Oid			relid;
 					CreateStatsStmt *stmt = (CreateStatsStmt *) parsetree;
-					RangeVar   *rel = (RangeVar *) linitial(stmt->relations);
+					List	   *relids = NIL;
+					ListCell   *cell;
 
-					if (!IsA(rel, RangeVar))
-						ereport(ERROR,
-								(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-								 errmsg("only a single relation is allowed in CREATE STATISTICS")));
+					foreach(cell, stmt->relations)
+					{
+						Oid			relid;
 
-					/*
-					 * 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);
+						if (!IsA(lfirst(cell), RangeVar))
+							ereport(ERROR,
+									errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+									errmsg("cannot create statistics on specified relation"),
+									errdetail("CREATE STATISTICS only supports tables, materialized views, foreign tables, and partitioned tables."));
 
+						/*
+						 * 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(castNode(RangeVar, lfirst(cell)),
+												 ShareUpdateExclusiveLock, false);
+						relids = lappend_oid(relids, relid);
+					}
 					/* Run parse analysis ... */
-					stmt = transformStatsStmt(relid, stmt, queryString);
+					stmt = transformStatsStmt(relids, stmt, queryString);
 
-					address = CreateStatistics(stmt);
+					/* ... and execute the command */
+					address = CreateStatistics(stmt, relids);
 				}
 				break;
 
diff --git a/src/include/commands/defrem.h b/src/include/commands/defrem.h
index dd22b5efdfd..7b8cb40cd83 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, List *relids);
 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 9f2b58de797..28165eb1198 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(List *relids, CreateStatsStmt *stmt,
 										   const char *queryString);
 extern void transformRuleStmt(RuleStmt *stmt, const char *queryString,
 							  List **actions, Node **whereClause);
-- 
2.39.5

From 0ad9908e2ad2762445807136784b18777fac4c87 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C3=81lvaro=20Herrera?= <alvherre@kurilemu.de>
Date: Thu, 28 Aug 2025 19:53:44 +0200
Subject: [PATCH] CREATE STATISTICS: Fix error message

---
 src/backend/tcop/utility.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/backend/tcop/utility.c b/src/backend/tcop/utility.c
index 25fe3d58016..7f5076d2c1a 100644
--- a/src/backend/tcop/utility.c
+++ b/src/backend/tcop/utility.c
@@ -1883,7 +1883,8 @@ ProcessUtilitySlow(ParseState *pstate,
 					if (!IsA(rel, RangeVar))
 						ereport(ERROR,
 								(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-								 errmsg("only a single relation is allowed in CREATE STATISTICS")));
+								 errmsg("cannot create statistics on specified relation"),
+								 errdetail("CREATE STATISTICS only supports tables, materialized views, foreign tables, and partitioned tables.")));
 
 					/*
 					 * CREATE STATISTICS will influence future execution plans
-- 
2.39.5

From 04975c4b93e60e2554b3d247d9bc38b5385530a3 Mon Sep 17 00:00:00 2001
From: jian he <jian.universality@gmail.com>
Date: Fri, 29 Aug 2025 12:03:49 +0800
Subject: [PATCH v2 1/1] refactor CreateStatsStmt

discussion: https://postgr.es/m/
---
 src/backend/commands/statscmds.c        | 14 ++++++++++++--
 src/backend/commands/tablecmds.c        |  2 +-
 src/backend/tcop/utility.c              | 25 +------------------------
 src/include/commands/defrem.h           |  2 +-
 src/test/regress/expected/stats_ext.out | 20 ++++++++++++++++++++
 src/test/regress/sql/stats_ext.sql      | 12 ++++++++++++
 6 files changed, 47 insertions(+), 28 deletions(-)

diff --git a/src/backend/commands/statscmds.c b/src/backend/commands/statscmds.c
index e24d540cd45..094d1a4fc1b 100644
--- a/src/backend/commands/statscmds.c
+++ b/src/backend/commands/statscmds.c
@@ -29,6 +29,7 @@
 #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"
@@ -57,9 +58,11 @@ compare_int16(const void *a, const void *b)
 
 /*
  *		CREATE STATISTICS
+ * ensure queryString is not NULL when we need do parse analysis for stmt!
+ * stmt changed on the go, espepcially transformStatsStmt.
  */
 ObjectAddress
-CreateStatistics(CreateStatsStmt *stmt)
+CreateStatistics(CreateStatsStmt *stmt, const char *queryString)
 {
 	int16		attnums[STATS_MAX_DIMENSIONS];
 	int			nattnums = 0;
@@ -112,7 +115,8 @@ 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("cannot create statistics on specified relation"),
+					 errdetail("CREATE STATISTICS only supports tables, materialized views, foreign tables, and partitioned tables")));
 
 		/*
 		 * CREATE STATISTICS will influence future execution plans but does
@@ -150,6 +154,12 @@ CreateStatistics(CreateStatsStmt *stmt)
 	Assert(rel);
 	relid = RelationGetRelid(rel);
 
+	if (queryString != NULL && !stmt->transformed)
+	{
+		/* Run parse analysis ... */
+		(void) transformStatsStmt(relid, 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 082a3575d62..b8dd9306b93 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -9654,7 +9654,7 @@ ATExecAddStatistics(AlteredTableInfo *tab, Relation rel,
 	/* The CreateStatsStmt has already been through transformStatsStmt */
 	Assert(stmt->transformed);
 
-	address = CreateStatistics(stmt);
+	address = CreateStatistics(stmt, NULL);
 
 	return address;
 }
diff --git a/src/backend/tcop/utility.c b/src/backend/tcop/utility.c
index 4f4191b0ea6..8d35ae971d5 100644
--- a/src/backend/tcop/utility.c
+++ b/src/backend/tcop/utility.c
@@ -1867,32 +1867,9 @@ ProcessUtilitySlow(ParseState *pstate,
 
 			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("only a single relation is allowed in CREATE STATISTICS")));
-
-					/*
-					 * 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(stmt, queryString);
 				}
 				break;
 
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/test/regress/expected/stats_ext.out b/src/test/regress/expected/stats_ext.out
index c66e09f8b16..fb920312b4d 100644
--- a/src/test/regress/expected/stats_ext.out
+++ b/src/test/regress/expected/stats_ext.out
@@ -88,6 +88,26 @@ ERROR:  statistics creation on system columns is not supported
 -- statistics without a less-than operator not supported
 CREATE STATISTICS tst (ndistinct) ON w from ext_stats_test1;
 ERROR:  column "w" cannot be used in statistics because its type xid has no default btree operator class
+CREATE STATISTICS tst ON (x is not null) FROM ext_stats_test s, lateral(values(s.x));
+ERROR:  only a single relation is allowed in CREATE STATISTICS
+CREATE STATISTICS tst ON (x is not null) FROM (SELECT * FROM ext_stats_test);
+ERROR:  cannot create statistics on specified relation
+DETAIL:  CREATE STATISTICS only supports tables, materialized views, foreign tables, and partitioned tables
+CREATE STATISTICS tst ON (x is not null) FROM ext_stats_test s TABLESAMPLE system (x) REPEATABLE (200);
+ERROR:  cannot create statistics on specified relation
+DETAIL:  CREATE STATISTICS only supports tables, materialized views, foreign tables, and partitioned tables
+CREATE STATISTICS tst ON (x is not null) FROM JSON_TABLE(jsonb '123', '$' COLUMNS (item int PATH '$'));
+ERROR:  cannot create statistics on specified relation
+DETAIL:  CREATE STATISTICS only supports tables, materialized views, foreign tables, and partitioned tables
+CREATE FUNCTION tftest(int) returns table(a int, b int) as $$
+BEGIN
+  RETURN QUERY SELECT $1, $1+i FROM generate_series(1,5) g(i);
+END;
+$$ LANGUAGE plpgsql IMMUTABLE STRICT;
+CREATE STATISTICS alt_stat2 ON a, b FROM tftest(1);
+ERROR:  cannot create statistics on specified relation
+DETAIL:  CREATE STATISTICS only supports tables, materialized views, foreign tables, and partitioned tables
+DROP FUNCTION tftest;
 DROP TABLE ext_stats_test1;
 -- Ensure stats are dropped sanely, and test IF NOT EXISTS while at it
 CREATE TABLE ab1 (a INTEGER, b INTEGER, c INTEGER);
diff --git a/src/test/regress/sql/stats_ext.sql b/src/test/regress/sql/stats_ext.sql
index 9ce4c670ecb..f63048f4c96 100644
--- a/src/test/regress/sql/stats_ext.sql
+++ b/src/test/regress/sql/stats_ext.sql
@@ -58,6 +58,18 @@ CREATE STATISTICS tst on (tableoid::int+1) from ext_stats_test1;
 CREATE STATISTICS tst (ndistinct) ON xmin from ext_stats_test1;
 -- statistics without a less-than operator not supported
 CREATE STATISTICS tst (ndistinct) ON w from ext_stats_test1;
+
+CREATE STATISTICS tst ON (x is not null) FROM ext_stats_test s, lateral(values(s.x));
+CREATE STATISTICS tst ON (x is not null) FROM (SELECT * FROM ext_stats_test);
+CREATE STATISTICS tst ON (x is not null) FROM ext_stats_test s TABLESAMPLE system (x) REPEATABLE (200);
+CREATE STATISTICS tst ON (x is not null) FROM JSON_TABLE(jsonb '123', '$' COLUMNS (item int PATH '$'));
+CREATE FUNCTION tftest(int) returns table(a int, b int) as $$
+BEGIN
+  RETURN QUERY SELECT $1, $1+i FROM generate_series(1,5) g(i);
+END;
+$$ LANGUAGE plpgsql IMMUTABLE STRICT;
+CREATE STATISTICS alt_stat2 ON a, b FROM tftest(1);
+DROP FUNCTION tftest;
 DROP TABLE ext_stats_test1;
 
 -- Ensure stats are dropped sanely, and test IF NOT EXISTS while at it
-- 
2.34.1

From f11f1c97ef4a18a31d5442e4e745a530caa02d07 Mon Sep 17 00:00:00 2001
From: jian he <jian.universality@gmail.com>
Date: Thu, 4 Sep 2025 12:52:13 +0800
Subject: [PATCH v3 1/1] refactor CreateStatsStmt

move all CreateStatsStmt logic into CreateStatistics.
Previously, CreateStatistics and ProcessUtilitySlow opened the same relation
twice with a ShareUpdateExclusiveLock.  This refactor ensures the relation is
opened with ShareUpdateExclusiveLock only once and also reduces redundant error
checks.
The logic is now more intuitive: we first error checking
CreateStatsStmt->relations and then call transformStatsStmt to parse analysis
CreateStatsStmt->exprs.

discussion: https://postgr.es/m/CACJufxFcvo=fM6J9RC88n1U=eS9+5QdftwUNQMu5h7OgjmqDwQ@mail.gmail.com
---
 src/backend/commands/statscmds.c | 17 ++++++++++++++---
 src/backend/commands/tablecmds.c |  2 +-
 src/backend/tcop/utility.c       | 30 +-----------------------------
 src/include/commands/defrem.h    |  2 +-
 4 files changed, 17 insertions(+), 34 deletions(-)

diff --git a/src/backend/commands/statscmds.c b/src/backend/commands/statscmds.c
index e24d540cd45..100eb82db64 100644
--- a/src/backend/commands/statscmds.c
+++ b/src/backend/commands/statscmds.c
@@ -29,6 +29,7 @@
 #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"
@@ -57,9 +58,11 @@ compare_int16(const void *a, const void *b)
 
 /*
  *		CREATE STATISTICS
+ * Ensure queryString is not NULL when we need do parse analysis for stmt!
+ * stmt changed on the go, see transformStatsStmt.
  */
 ObjectAddress
-CreateStatistics(CreateStatsStmt *stmt)
+CreateStatistics(CreateStatsStmt *stmt, const char *queryString)
 {
 	int16		attnums[STATS_MAX_DIMENSIONS];
 	int			nattnums = 0;
@@ -111,8 +114,9 @@ CreateStatistics(CreateStatsStmt *stmt)
 
 		if (!IsA(rln, RangeVar))
 			ereport(ERROR,
-					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-					 errmsg("only a single relation is allowed in CREATE STATISTICS")));
+					errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+					errmsg("cannot create statistics on the specified relation"),
+					errdetail("CREATE STATISTICS only supports tables, foreign tables and materialized views."));
 
 		/*
 		 * CREATE STATISTICS will influence future execution plans but does
@@ -150,6 +154,13 @@ CreateStatistics(CreateStatsStmt *stmt)
 	Assert(rel);
 	relid = RelationGetRelid(rel);
 
+	if (queryString != NULL)
+	{
+		/* Run parse analysis ... */
+		(void) transformStatsStmt(relid, stmt, queryString);
+	}
+	Assert(stmt->transformed);
+
 	/*
 	 * 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 082a3575d62..b8dd9306b93 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -9654,7 +9654,7 @@ ATExecAddStatistics(AlteredTableInfo *tab, Relation rel,
 	/* The CreateStatsStmt has already been through transformStatsStmt */
 	Assert(stmt->transformed);
 
-	address = CreateStatistics(stmt);
+	address = CreateStatistics(stmt, NULL);
 
 	return address;
 }
diff --git a/src/backend/tcop/utility.c b/src/backend/tcop/utility.c
index 5f442bc3bd4..027356f6e77 100644
--- a/src/backend/tcop/utility.c
+++ b/src/backend/tcop/utility.c
@@ -1866,35 +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("cannot create statistics on the specified relation"),
-								 errdetail("CREATE STATISTICS only supports tables, foreign tables and materialized views.")));
-
-					/*
-					 * 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);
-- 
2.34.1

From 7c55d765dc1ec2f8a28e8ae1fe3551d32ed5a964 Mon Sep 17 00:00:00 2001
From: Peter Eisentraut <peter@eisentraut.org>
Date: Fri, 12 Sep 2025 15:30:16 +0200
Subject: [PATCH v4] CREATE STATISTICS: improve misleading error message

The previous change (commit f225473cbae) was still not on target,
because it talked about relation kinds, which are not what is being
checked here.  Provide a more accurate message.

Discussion: https://postgr.es/m/CACJufxEZ48toGH0Em_6vdsT57Y3L8pLF=DZCQ_gCii6=C3MeXw@mail.gmail.com
---
 src/backend/tcop/utility.c              |  5 ++---
 src/test/regress/expected/stats_ext.out | 21 +++++++--------------
 2 files changed, 9 insertions(+), 17 deletions(-)

diff --git a/src/backend/tcop/utility.c b/src/backend/tcop/utility.c
index 5f442bc3bd4..68605656b31 100644
--- a/src/backend/tcop/utility.c
+++ b/src/backend/tcop/utility.c
@@ -1873,9 +1873,8 @@ ProcessUtilitySlow(ParseState *pstate,
 
 					if (!IsA(rel, RangeVar))
 						ereport(ERROR,
-								(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-								 errmsg("cannot create statistics on the specified relation"),
-								 errdetail("CREATE STATISTICS only supports tables, foreign tables and materialized views.")));
+								(errcode(ERRCODE_SYNTAX_ERROR),
+								 errmsg("CREATE STATISTICS only supports relation names in the FROM clause")));
 
 					/*
 					 * CREATE STATISTICS will influence future execution plans
diff --git a/src/test/regress/expected/stats_ext.out b/src/test/regress/expected/stats_ext.out
index a1f83b58b23..fdc0aa130bd 100644
--- a/src/test/regress/expected/stats_ext.out
+++ b/src/test/regress/expected/stats_ext.out
@@ -56,29 +56,22 @@ CREATE STATISTICS tst (unrecognized) ON x, y FROM ext_stats_test;
 ERROR:  unrecognized statistics kind "unrecognized"
 -- unsupported targets
 CREATE STATISTICS tst ON a FROM (VALUES (x)) AS foo;
-ERROR:  cannot create statistics on the specified relation
-DETAIL:  CREATE STATISTICS only supports tables, foreign tables and materialized views.
+ERROR:  CREATE STATISTICS only supports relation names in the FROM clause
 CREATE STATISTICS tst ON a FROM foo NATURAL JOIN bar;
-ERROR:  cannot create statistics on the specified relation
-DETAIL:  CREATE STATISTICS only supports tables, foreign tables and materialized views.
+ERROR:  CREATE STATISTICS only supports relation names in the FROM clause
 CREATE STATISTICS tst ON a FROM (SELECT * FROM ext_stats_test) AS foo;
-ERROR:  cannot create statistics on the specified relation
-DETAIL:  CREATE STATISTICS only supports tables, foreign tables and materialized views.
+ERROR:  CREATE STATISTICS only supports relation names in the FROM clause
 CREATE STATISTICS tst ON a FROM ext_stats_test s TABLESAMPLE system (x);
-ERROR:  cannot create statistics on the specified relation
-DETAIL:  CREATE STATISTICS only supports tables, foreign tables and materialized views.
+ERROR:  CREATE STATISTICS only supports relation names in the FROM clause
 CREATE STATISTICS tst ON a FROM XMLTABLE('foo' PASSING 'bar' COLUMNS a text);
-ERROR:  cannot create statistics on the specified relation
-DETAIL:  CREATE STATISTICS only supports tables, foreign tables and materialized views.
+ERROR:  CREATE STATISTICS only supports relation names in the FROM clause
 CREATE STATISTICS tst ON a FROM JSON_TABLE(jsonb '123', '$' COLUMNS (item int));
-ERROR:  cannot create statistics on the specified relation
-DETAIL:  CREATE STATISTICS only supports tables, foreign tables and materialized views.
+ERROR:  CREATE STATISTICS only supports relation names in the FROM clause
 CREATE FUNCTION tftest(int) returns table(a int, b int) as $$
 SELECT $1, $1+i FROM generate_series(1,5) g(i);
 $$ LANGUAGE sql IMMUTABLE STRICT;
 CREATE STATISTICS alt_stat2 ON a FROM tftest(1);
-ERROR:  cannot create statistics on the specified relation
-DETAIL:  CREATE STATISTICS only supports tables, foreign tables and materialized views.
+ERROR:  CREATE STATISTICS only supports relation names in the FROM clause
 DROP FUNCTION tftest;
 -- incorrect expressions
 CREATE STATISTICS tst ON (y) FROM ext_stats_test; -- single column reference
-- 
2.51.0

From 929e3d9a1bcf36937b1f362963f78595bfd47f88 Mon Sep 17 00:00:00 2001
From: jian he <jian.universality@gmail.com>
Date: Thu, 2 Oct 2025 11:24:40 +0800
Subject: [PATCH v5 1/1] refactor CreateStatsStmt

move all CreateStatsStmt logic into CreateStatistics.
Previously, CreateStatistics and ProcessUtilitySlow opened the same relation
twice with a ShareUpdateExclusiveLock.  This refactor ensures the relation is
opened with ShareUpdateExclusiveLock only once and also remove redundant error
checks.

in function: CreateStatsStmt we first error checking CreateStatsStmt->relations
and then call transformStatsStmt to parse analysis CreateStatsStmt->exprs.

discussion: https://postgr.es/m/CACJufxFcvo=fM6J9RC88n1U=eS9+5QdftwUNQMu5h7OgjmqDwQ@mail.gmail.com
---
 src/backend/commands/statscmds.c | 14 ++++++++++++--
 src/backend/commands/tablecmds.c |  2 +-
 src/backend/tcop/utility.c       | 29 +----------------------------
 src/include/commands/defrem.h    |  2 +-
 4 files changed, 15 insertions(+), 32 deletions(-)

diff --git a/src/backend/commands/statscmds.c b/src/backend/commands/statscmds.c
index e24d540cd45..400bb293fa4 100644
--- a/src/backend/commands/statscmds.c
+++ b/src/backend/commands/statscmds.c
@@ -29,6 +29,7 @@
 #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"
@@ -57,9 +58,12 @@ compare_int16(const void *a, const void *b)
 
 /*
  *		CREATE STATISTICS
+  * queryString is the source text of the CREATE STATISTICS command;
+  * It must be supplied if the CreateStatsStmt not being transformed
+  * (run transformStatsStmt), else it can be NULL.
  */
 ObjectAddress
-CreateStatistics(CreateStatsStmt *stmt)
+CreateStatistics(CreateStatsStmt *stmt, const char *queryString)
 {
 	int16		attnums[STATS_MAX_DIMENSIONS];
 	int			nattnums = 0;
@@ -112,7 +116,7 @@ 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
@@ -150,6 +154,12 @@ CreateStatistics(CreateStatsStmt *stmt)
 	Assert(rel);
 	relid = RelationGetRelid(rel);
 
+	/* Run parse analysis ... */
+	if (queryString != NULL)
+		stmt = transformStatsStmt(relid, stmt, queryString);
+
+	Assert(stmt->transformed);
+
 	/*
 	 * 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 fc89352b661..19c11970787 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -9658,7 +9658,7 @@ ATExecAddStatistics(AlteredTableInfo *tab, Relation rel,
 	/* The CreateStatsStmt has already been through transformStatsStmt */
 	Assert(stmt->transformed);
 
-	address = CreateStatistics(stmt);
+	address = CreateStatistics(stmt, NULL);
 
 	return address;
 }
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);
-- 
2.34.1

From 4e690419874eb128bb3371f9c39ed95d8e731f64 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C3=81lvaro=20Herrera?= <alvherre@kurilemu.de>
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 <jian.universality@gmail.com>
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

From 1f6c467793843354e492cc7b5cd7e1137822250a Mon Sep 17 00:00:00 2001
From: jian he <jian.universality@gmail.com>
Date: Thu, 13 Nov 2025 11:19:26 +0800
Subject: [PATCH v5 1/1] 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.

Generally we should avoid look up the same less-than-fully-qualified name
multiple times, we might get different answers due to concurrent activity, and
that might create a security vulnerability, along the lines of CVE-2014-0062.

Refactor so that a CreateStatsStmt carries both the untransformed FROM clause
and the range table that we get when it's transformed. That way, once the name
lookups have been done, we can propagate the results forward to future
processing steps and avoid ever repeating the lookup.

discussion: https://postgr.es/m/CACJufxGXLU400QBBgdoboaza0xK58rQqsCAPrxbAMUmo0f8xCQ@mail.gmail.com
discussion: https://postgr.es/m/CA+TgmobyMXzoEzscCRDCggHRCTp1TW=Dm9pEhmwOYKos43WDAg@mail.gmail.com
commitfest: https://commitfest.postgresql.org/patch/6106
---
 src/backend/commands/statscmds.c   |  65 ++++------------
 src/backend/commands/tablecmds.c   |  17 ++++-
 src/backend/parser/gram.y          |   6 +-
 src/backend/parser/parse_utilcmd.c | 118 +++++++++++++++++++++++++++--
 src/backend/tcop/utility.c         |  29 +------
 src/include/commands/defrem.h      |   2 +-
 src/include/nodes/parsenodes.h     |   3 +
 src/include/parser/parse_utilcmd.h |   3 +-
 8 files changed, 150 insertions(+), 93 deletions(-)

diff --git a/src/backend/commands/statscmds.c b/src/backend/commands/statscmds.c
index 0cf0ea43f19..0e08229de53 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"
@@ -60,7 +61,7 @@ compare_int16(const void *a, const void *b)
  *		CREATE STATISTICS
  */
 ObjectAddress
-CreateStatistics(CreateStatsStmt *stmt, bool check_rights)
+CreateStatistics(CreateStatsStmt *stmt, bool check_rights, const char *queryString)
 {
 	int16		attnums[STATS_MAX_DIMENSIONS];
 	int			nattnums = 0;
@@ -78,6 +79,7 @@ CreateStatistics(CreateStatsStmt *stmt, bool check_rights)
 	Datum		exprsDatum;
 	Relation	statrel;
 	Relation	rel = NULL;
+	RangeTblEntry *rte;
 	Oid			relid;
 	ObjectAddress parentobject,
 				myself;
@@ -95,58 +97,23 @@ CreateStatistics(CreateStatsStmt *stmt, bool check_rights)
 
 	Assert(IsA(stmt, CreateStatsStmt));
 
+	/* Run parse analysis */
+	stmt = transformStatsStmt(stmt, queryString);
+
+	/* XXX internal error is better than Assert? error message need polish */
+	if (list_length(stmt->rtable) != list_length(stmt->from_clause))
+		elog(ERROR, "CreateStatsStmt length of rtable should equal to from_clause");
+
 	/*
-	 * Examine the FROM clause.  Currently, we only allow it to be a single
-	 * simple table, but later we'll probably allow multiple tables and JOIN
-	 * syntax.  The grammar is already prepared for that, so we have to check
-	 * here that what we got is what we can support.
+	 * Double-check that the range table is of a form we can support.
 	 */
-	if (list_length(stmt->relations) != 1)
+	if (list_length(stmt->rtable) != 1)
 		ereport(ERROR,
-				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-				 errmsg("only a single relation is allowed in CREATE STATISTICS")));
+				errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+				errmsg("only a single relation is allowed in CREATE STATISTICS"));
 
-	foreach(cell, stmt->relations)
-	{
-		Node	   *rln = (Node *) lfirst(cell);
-
-		if (!IsA(rln, RangeVar))
-			ereport(ERROR,
-					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-					 errmsg("only a single relation is allowed in CREATE STATISTICS")));
-
-		/*
-		 * CREATE STATISTICS will influence future execution plans but does
-		 * not interfere with currently executing plans.  So it should be
-		 * enough to take only ShareUpdateExclusiveLock on relation,
-		 * conflicting with ANALYZE and other DDL that sets statistical
-		 * information, but not with normal queries.
-		 */
-		rel = relation_openrv((RangeVar *) rln, ShareUpdateExclusiveLock);
-
-		/* Restrict to allowed relation types */
-		if (rel->rd_rel->relkind != RELKIND_RELATION &&
-			rel->rd_rel->relkind != RELKIND_MATVIEW &&
-			rel->rd_rel->relkind != RELKIND_FOREIGN_TABLE &&
-			rel->rd_rel->relkind != RELKIND_PARTITIONED_TABLE)
-			ereport(ERROR,
-					(errcode(ERRCODE_WRONG_OBJECT_TYPE),
-					 errmsg("cannot define statistics for relation \"%s\"",
-							RelationGetRelationName(rel)),
-					 errdetail_relkind_not_supported(rel->rd_rel->relkind)));
-
-		/* You must own the relation to create stats on it */
-		if (!object_ownercheck(RelationRelationId, RelationGetRelid(rel), stxowner))
-			aclcheck_error(ACLCHECK_NOT_OWNER, get_relkind_objtype(rel->rd_rel->relkind),
-						   RelationGetRelationName(rel));
-
-		/* Creating statistics on system catalogs is not allowed */
-		if (!allowSystemTableMods && IsSystemRelation(rel))
-			ereport(ERROR,
-					(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
-					 errmsg("permission denied: \"%s\" is a system catalog",
-							RelationGetRelationName(rel))));
-	}
+	rte = linitial_node(RangeTblEntry, stmt->rtable);
+	rel = relation_open(rte->relid, NoLock);
 
 	Assert(rel);
 	relid = RelationGetRelid(rel);
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index 23ebaa3f230..5d778f8d7d6 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -9682,7 +9682,7 @@ ATExecAddStatistics(AlteredTableInfo *tab, Relation rel,
 	/* The CreateStatsStmt has already been through transformStatsStmt */
 	Assert(stmt->transformed);
 
-	address = CreateStatistics(stmt, !is_rebuild);
+	address = CreateStatistics(stmt, !is_rebuild, NULL);
 
 	return address;
 }
@@ -15658,10 +15658,19 @@ ATPostAlterTypeParse(Oid oldId, Oid oldRelId, Oid refRelId, char *cmd,
 			querytree_list = list_concat(querytree_list, afterStmts);
 		}
 		else if (IsA(stmt, CreateStatsStmt))
+		{
+			RangeTblEntry 	*rte;
+			CreateStatsStmt *ss = castNode(CreateStatsStmt, stmt);
+
+			rte = makeNode(RangeTblEntry);
+			rte->rtekind = RTE_RELATION;
+			rte->relid = oldRelId;
+			rte->rellockmode = ShareUpdateExclusiveLock;
+			ss->rtable = list_make1(rte);
+
 			querytree_list = lappend(querytree_list,
-									 transformStatsStmt(oldRelId,
-														(CreateStatsStmt *) stmt,
-														cmd));
+									 transformStatsStmt(ss, cmd));
+		}
 		else
 			querytree_list = lappend(querytree_list, stmt);
 	}
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index c3a0a354a9c..ca3cb446acd 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -4778,7 +4778,8 @@ CreateStatsStmt:
 					n->defnames = $3;
 					n->stat_types = $4;
 					n->exprs = $6;
-					n->relations = $8;
+					n->from_clause = $8;
+					n->rtable = NIL;
 					n->stxcomment = NULL;
 					n->if_not_exists = false;
 					$$ = (Node *) n;
@@ -4791,7 +4792,8 @@ CreateStatsStmt:
 					n->defnames = $6;
 					n->stat_types = $7;
 					n->exprs = $9;
-					n->relations = $11;
+					n->from_clause = $11;
+					n->rtable = NIL;
 					n->stxcomment = NULL;
 					n->if_not_exists = true;
 					$$ = (Node *) n;
diff --git a/src/backend/parser/parse_utilcmd.c b/src/backend/parser/parse_utilcmd.c
index e96b38a59d5..410d8e84e87 100644
--- a/src/backend/parser/parse_utilcmd.c
+++ b/src/backend/parser/parse_utilcmd.c
@@ -2049,6 +2049,7 @@ generateClonedExtStatsStmt(RangeVar *heapRel, Oid heapRelid,
 	HeapTuple	ht_stats;
 	Form_pg_statistic_ext statsrec;
 	CreateStatsStmt *stats;
+	RangeTblEntry 	*rte;
 	List	   *stat_types = NIL;
 	List	   *def_names = NIL;
 	bool		isnull;
@@ -2152,7 +2153,15 @@ generateClonedExtStatsStmt(RangeVar *heapRel, Oid heapRelid,
 	stats->defnames = NULL;
 	stats->stat_types = stat_types;
 	stats->exprs = def_names;
-	stats->relations = list_make1(heapRel);
+	stats->from_clause = list_make1(heapRel);
+
+	/* Create a range table entry. */
+	rte = makeNode(RangeTblEntry);
+	rte->rtekind = RTE_RELATION;
+	rte->relid = heapRelid;
+	rte->rellockmode = ShareUpdateExclusiveLock;
+	stats->rtable = list_make1(rte);
+
 	stats->stxcomment = NULL;
 	stats->transformed = true;	/* don't need transformStatsStmt again */
 	stats->if_not_exists = false;
@@ -3136,32 +3145,46 @@ 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.
+ * This is used by CREATE STATISTICS. Changing table column’s data type or
+ * generated expression will trigger a rebuild of the related table’s
+ * statistics, during which this will also be used.
  */
 CreateStatsStmt *
-transformStatsStmt(Oid relid, CreateStatsStmt *stmt, const char *queryString)
+transformStatsStmt(CreateStatsStmt *stmt, const char *queryString)
 {
 	ParseState *pstate;
 	ParseNamespaceItem *nsitem;
 	ListCell   *l;
 	Relation	rel;
+	RangeTblEntry *rte;
 
 	/* Nothing to do if statement already transformed. */
 	if (stmt->transformed)
 		return stmt;
 
+	/* Construct range table if not done yet. */
+	if (stmt->rtable == NIL)
+		stmt->rtable = transformStatsFromClause(stmt->from_clause);
+
+	/*
+	 * The range table should have been derived from a FROM clause consisting
+	 * of a single RangeVar, so we expect a single RangeTblEntry.
+	 */
+	Assert(list_length(stmt->rtable) == 1);
+	rte = linitial(stmt->rtable);
+	Assert(IsA(rte, RangeTblEntry));
+
+	/* See transformStatsFromClause for notes on lock level. */
+	rel = table_open(rte->relid, NoLock);
+
 	/* Set up pstate */
 	pstate = make_parsestate(NULL);
 	pstate->p_sourcetext = 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);
@@ -3205,6 +3228,85 @@ transformStatsStmt(Oid relid, CreateStatsStmt *stmt, const char *queryString)
 	return stmt;
 }
 
+/*
+ * Accepts a list of RangeVar objects and returns a corresponding list of
+ * RangeTblEntry objects. For use while transforming a CreateStatsStmt.
+ *
+ * At present, the only case we know how to handle is a FROM clause
+ * consisting of a single RangeVar.
+ */
+List *
+transformStatsFromClause(List *from_clause)
+{
+	RangeTblEntry *rte;
+	ListCell   *cell;
+	Relation	rel = NULL;
+
+	/*
+	 * Examine the FROM clause.  Currently, we only allow it to be a single
+	 * simple table, but later we'll probably allow multiple tables and JOIN
+	 * syntax.  The grammar is already prepared for that, so we have to check
+	 * here that what we got is what we can support.
+	 */
+	if (list_length(from_clause) != 1)
+		ereport(ERROR,
+				errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+				errmsg("only a single relation is allowed in CREATE STATISTICS"));
+
+	foreach(cell, from_clause)
+	{
+		Node	   *rln = (Node *) lfirst(cell);
+
+		if (!IsA(rln, 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 only ShareUpdateExclusiveLock on relation,
+		 * conflicting with ANALYZE and other DDL that sets statistical
+		 * information, but not with normal queries.
+		 */
+		rel = relation_openrv((RangeVar *) rln, ShareUpdateExclusiveLock);
+
+		/* Restrict to allowed relation types */
+		if (rel->rd_rel->relkind != RELKIND_RELATION &&
+			rel->rd_rel->relkind != RELKIND_MATVIEW &&
+			rel->rd_rel->relkind != RELKIND_FOREIGN_TABLE &&
+			rel->rd_rel->relkind != RELKIND_PARTITIONED_TABLE)
+			ereport(ERROR,
+					errcode(ERRCODE_WRONG_OBJECT_TYPE),
+					errmsg("cannot define statistics for relation \"%s\"",
+						   RelationGetRelationName(rel)),
+					errdetail_relkind_not_supported(rel->rd_rel->relkind));
+
+		/* You must own the relation to create stats on it */
+		if (!object_ownercheck(RelationRelationId, RelationGetRelid(rel), GetUserId()))
+			aclcheck_error(ACLCHECK_NOT_OWNER, get_relkind_objtype(rel->rd_rel->relkind),
+						   RelationGetRelationName(rel));
+
+		/* Creating statistics on system catalogs is not allowed */
+		if (!allowSystemTableMods && IsSystemRelation(rel))
+			ereport(ERROR,
+					errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
+					errmsg("permission denied: \"%s\" is a system catalog",
+						   RelationGetRelationName(rel)));
+	}
+
+	/* Create a range table entry. */
+	rte = makeNode(RangeTblEntry);
+	rte->rtekind = RTE_RELATION;
+	rte->relid = RelationGetRelid(rel);
+	rte->rellockmode = ShareUpdateExclusiveLock;
+
+	/* Close relation */
+	relation_close(rel, NoLock);
+
+	return list_make1(rte);
+}
+
 
 /*
  * transformRuleStmt -
diff --git a/src/backend/tcop/utility.c b/src/backend/tcop/utility.c
index d18a3a60a46..0c31113ebb5 100644
--- a/src/backend/tcop/utility.c
+++ b/src/backend/tcop/utility.c
@@ -1874,34 +1874,7 @@ 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, true);
-				}
+				address = CreateStatistics((CreateStatsStmt *) parsetree, true, queryString);
 				break;
 
 			case T_AlterStatsStmt:
diff --git a/src/include/commands/defrem.h b/src/include/commands/defrem.h
index f3432b4b6a1..95397f91c5a 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, bool check_rights);
+extern ObjectAddress CreateStatistics(CreateStatsStmt *stmt, bool check_rights, 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/nodes/parsenodes.h b/src/include/nodes/parsenodes.h
index d14294a4ece..3e9257cc8ae 100644
--- a/src/include/nodes/parsenodes.h
+++ b/src/include/nodes/parsenodes.h
@@ -3523,6 +3523,9 @@ typedef struct CreateStatsStmt
 	List	   *stat_types;		/* stat types (list of String) */
 	List	   *exprs;			/* expressions to build statistics on */
 	List	   *relations;		/* rels to build stats on (list of RangeVar) */
+	List	   *from_clause;	/* FROM clause ((list of RangeVar)) */
+	List	   *rtable;			/* It’s not derived directly from the parser, instead
+								 * it comes from parse analysis. (list of RangeTblEntry) */
 	char	   *stxcomment;		/* comment to apply to stats, or NULL */
 	bool		transformed;	/* true when transformStatsStmt is finished */
 	bool		if_not_exists;	/* do nothing if stats name already exists */
diff --git a/src/include/parser/parse_utilcmd.h b/src/include/parser/parse_utilcmd.h
index 4965fac4495..499e9ebef1c 100644
--- a/src/include/parser/parse_utilcmd.h
+++ b/src/include/parser/parse_utilcmd.h
@@ -26,8 +26,9 @@ 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(CreateStatsStmt *stmt,
 										   const char *queryString);
+extern List *transformStatsFromClause(List *from_clause);
 extern void transformRuleStmt(RuleStmt *stmt, const char *queryString,
 							  List **actions, Node **whereClause);
 extern List *transformCreateSchemaStmtElements(List *schemaElts,
-- 
2.34.1

From e9e4a0a85b3244da89e45ba7f258e57c109c3610 Mon Sep 17 00:00:00 2001
From: jian he <jian.universality@gmail.com>
Date: Wed, 17 Dec 2025 13:44:46 +0800
Subject: [PATCH v6 1/1] 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.

Generally we should avoid look up the same less-than-fully-qualified name
multiple times, we might get different answers due to concurrent activity, and
that might create a security vulnerability, along the lines of CVE-2014-0062.

Refactor so that a CreateStatsStmt carries both the untransformed FROM clause
and the range table that we get when it's transformed. That way, once the name
lookups have been done, we can propagate the results forward to future
processing steps and avoid ever repeating the lookup.

discussion: https://postgr.es/m/CACJufxGXLU400QBBgdoboaza0xK58rQqsCAPrxbAMUmo0f8xCQ@mail.gmail.com
discussion: https://postgr.es/m/CA+TgmobyMXzoEzscCRDCggHRCTp1TW=Dm9pEhmwOYKos43WDAg@mail.gmail.com
commitfest: https://commitfest.postgresql.org/patch/6106
---
 src/backend/commands/statscmds.c   |  65 ++-------------
 src/backend/commands/tablecmds.c   |  17 +++-
 src/backend/parser/gram.y          |   6 +-
 src/backend/parser/parse_utilcmd.c | 124 +++++++++++++++++++++++++++--
 src/backend/tcop/utility.c         |  29 +------
 src/include/commands/defrem.h      |   2 +-
 src/include/nodes/parsenodes.h     |   4 +
 src/include/parser/parse_utilcmd.h |   3 +-
 8 files changed, 149 insertions(+), 101 deletions(-)

diff --git a/src/backend/commands/statscmds.c b/src/backend/commands/statscmds.c
index 77b1a6e2dc5..e323190cb11 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"
@@ -60,7 +61,7 @@ compare_int16(const void *a, const void *b)
  *		CREATE STATISTICS
  */
 ObjectAddress
-CreateStatistics(CreateStatsStmt *stmt, bool check_rights)
+CreateStatistics(CreateStatsStmt *stmt, bool check_rights, const char *queryString)
 {
 	int16		attnums[STATS_MAX_DIMENSIONS];
 	int			nattnums = 0;
@@ -78,6 +79,7 @@ CreateStatistics(CreateStatsStmt *stmt, bool check_rights)
 	Datum		exprsDatum;
 	Relation	statrel;
 	Relation	rel = NULL;
+	RangeTblEntry *rte;
 	Oid			relid;
 	ObjectAddress parentobject,
 				myself;
@@ -95,64 +97,13 @@ CreateStatistics(CreateStatsStmt *stmt, bool check_rights)
 
 	Assert(IsA(stmt, CreateStatsStmt));
 
-	/*
-	 * Examine the FROM clause.  Currently, we only allow it to be a single
-	 * simple table, but later we'll probably allow multiple tables and JOIN
-	 * syntax.  The grammar is already prepared for that, so we have to check
-	 * here that what we got is what we can support.
-	 */
-	if (list_length(stmt->relations) != 1)
-		ereport(ERROR,
-				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-				 errmsg("only a single relation is allowed in CREATE STATISTICS")));
+	/* Run parse analysis */
+	stmt = transformStatsStmt(stmt, queryString);
 
-	foreach(cell, stmt->relations)
-	{
-		Node	   *rln = (Node *) lfirst(cell);
+	Assert(list_length(stmt->rtable) == list_length(stmt->from_clause));
 
-		if (!IsA(rln, RangeVar))
-			ereport(ERROR,
-					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-					 errmsg("only a single relation is allowed in CREATE STATISTICS")));
-
-		/*
-		 * CREATE STATISTICS will influence future execution plans but does
-		 * not interfere with currently executing plans.  So it should be
-		 * enough to take only ShareUpdateExclusiveLock on relation,
-		 * conflicting with ANALYZE and other DDL that sets statistical
-		 * information, but not with normal queries.
-		 */
-		rel = relation_openrv((RangeVar *) rln, ShareUpdateExclusiveLock);
-
-		/* Restrict to allowed relation types */
-		if (rel->rd_rel->relkind != RELKIND_RELATION &&
-			rel->rd_rel->relkind != RELKIND_MATVIEW &&
-			rel->rd_rel->relkind != RELKIND_FOREIGN_TABLE &&
-			rel->rd_rel->relkind != RELKIND_PARTITIONED_TABLE)
-			ereport(ERROR,
-					(errcode(ERRCODE_WRONG_OBJECT_TYPE),
-					 errmsg("cannot define statistics for relation \"%s\"",
-							RelationGetRelationName(rel)),
-					 errdetail_relkind_not_supported(rel->rd_rel->relkind)));
-
-		/*
-		 * You must own the relation to create stats on it.
-		 *
-		 * NB: Concurrent changes could cause this function's lookup to find a
-		 * different relation than a previous lookup by the caller, so we must
-		 * perform this check even when check_rights == false.
-		 */
-		if (!object_ownercheck(RelationRelationId, RelationGetRelid(rel), stxowner))
-			aclcheck_error(ACLCHECK_NOT_OWNER, get_relkind_objtype(rel->rd_rel->relkind),
-						   RelationGetRelationName(rel));
-
-		/* Creating statistics on system catalogs is not allowed */
-		if (!allowSystemTableMods && IsSystemRelation(rel))
-			ereport(ERROR,
-					(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
-					 errmsg("permission denied: \"%s\" is a system catalog",
-							RelationGetRelationName(rel))));
-	}
+	rte = linitial_node(RangeTblEntry, stmt->rtable);
+	rel = relation_open(rte->relid, NoLock);
 
 	Assert(rel);
 	relid = RelationGetRelid(rel);
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index 6b1a00ed477..3fb9d9afe23 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -9718,7 +9718,7 @@ ATExecAddStatistics(AlteredTableInfo *tab, Relation rel,
 	/* The CreateStatsStmt has already been through transformStatsStmt */
 	Assert(stmt->transformed);
 
-	address = CreateStatistics(stmt, !is_rebuild);
+	address = CreateStatistics(stmt, !is_rebuild, NULL);
 
 	return address;
 }
@@ -15694,10 +15694,19 @@ ATPostAlterTypeParse(Oid oldId, Oid oldRelId, Oid refRelId, char *cmd,
 			querytree_list = list_concat(querytree_list, afterStmts);
 		}
 		else if (IsA(stmt, CreateStatsStmt))
+		{
+			RangeTblEntry *rte;
+			CreateStatsStmt *ss = castNode(CreateStatsStmt, stmt);
+
+			rte = makeNode(RangeTblEntry);
+			rte->rtekind = RTE_RELATION;
+			rte->relid = oldRelId;
+			rte->rellockmode = ShareUpdateExclusiveLock;
+			ss->rtable = list_make1(rte);
+
 			querytree_list = lappend(querytree_list,
-									 transformStatsStmt(oldRelId,
-														(CreateStatsStmt *) stmt,
-														cmd));
+									 transformStatsStmt(ss, cmd));
+		}
 		else
 			querytree_list = lappend(querytree_list, stmt);
 	}
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 28f4e11e30f..7a4ee97988d 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -4830,7 +4830,8 @@ CreateStatsStmt:
 					n->defnames = $3;
 					n->stat_types = $4;
 					n->exprs = $6;
-					n->relations = $8;
+					n->from_clause = $8;
+					n->rtable = NIL;
 					n->stxcomment = NULL;
 					n->if_not_exists = false;
 					$$ = (Node *) n;
@@ -4843,7 +4844,8 @@ CreateStatsStmt:
 					n->defnames = $6;
 					n->stat_types = $7;
 					n->exprs = $9;
-					n->relations = $11;
+					n->from_clause = $11;
+					n->rtable = NIL;
 					n->stxcomment = NULL;
 					n->if_not_exists = true;
 					$$ = (Node *) n;
diff --git a/src/backend/parser/parse_utilcmd.c b/src/backend/parser/parse_utilcmd.c
index 375b40b29af..0817c4e63f1 100644
--- a/src/backend/parser/parse_utilcmd.c
+++ b/src/backend/parser/parse_utilcmd.c
@@ -2052,6 +2052,7 @@ generateClonedExtStatsStmt(RangeVar *heapRel, Oid heapRelid,
 	HeapTuple	ht_stats;
 	Form_pg_statistic_ext statsrec;
 	CreateStatsStmt *stats;
+	RangeTblEntry *rte;
 	List	   *stat_types = NIL;
 	List	   *def_names = NIL;
 	bool		isnull;
@@ -2155,7 +2156,15 @@ generateClonedExtStatsStmt(RangeVar *heapRel, Oid heapRelid,
 	stats->defnames = NULL;
 	stats->stat_types = stat_types;
 	stats->exprs = def_names;
-	stats->relations = list_make1(heapRel);
+	stats->from_clause = list_make1(heapRel);
+
+	/* Create a range table entry. */
+	rte = makeNode(RangeTblEntry);
+	rte->rtekind = RTE_RELATION;
+	rte->relid = heapRelid;
+	rte->rellockmode = ShareUpdateExclusiveLock;
+	stats->rtable = list_make1(rte);
+
 	stats->stxcomment = NULL;
 	stats->transformed = true;	/* don't need transformStatsStmt again */
 	stats->if_not_exists = false;
@@ -3139,32 +3148,46 @@ 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.
+ * This is used by CREATE STATISTICS. Changing table column’s data type or
+ * generated expression will trigger a rebuild of the related table’s
+ * statistics, during which this will also be used.
  */
 CreateStatsStmt *
-transformStatsStmt(Oid relid, CreateStatsStmt *stmt, const char *queryString)
+transformStatsStmt(CreateStatsStmt *stmt, const char *queryString)
 {
 	ParseState *pstate;
 	ParseNamespaceItem *nsitem;
 	ListCell   *l;
 	Relation	rel;
+	RangeTblEntry *rte;
 
 	/* Nothing to do if statement already transformed. */
 	if (stmt->transformed)
 		return stmt;
 
+	/* Construct range table if not done yet. */
+	if (stmt->rtable == NIL)
+		stmt->rtable = transformStatsFromClause(stmt->from_clause);
+
+	/*
+	 * The range table should have been derived from a FROM clause consisting
+	 * of a single RangeVar, so we expect a single RangeTblEntry.
+	 */
+	Assert(list_length(stmt->rtable) == 1);
+	rte = linitial(stmt->rtable);
+	Assert(IsA(rte, RangeTblEntry));
+
+	/* See transformStatsFromClause for notes on lock level. */
+	rel = table_open(rte->relid, NoLock);
+
 	/* Set up pstate */
 	pstate = make_parsestate(NULL);
 	pstate->p_sourcetext = 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);
@@ -3208,6 +3231,91 @@ transformStatsStmt(Oid relid, CreateStatsStmt *stmt, const char *queryString)
 	return stmt;
 }
 
+/*
+ * Accepts a list of RangeVar objects and returns a corresponding list of
+ * RangeTblEntry objects. For use while transforming a CreateStatsStmt.
+ *
+ * At present, the only case we know how to handle is a FROM clause
+ * consisting of a single RangeVar.
+ */
+List *
+transformStatsFromClause(List *from_clause)
+{
+	RangeTblEntry *rte;
+	ListCell   *cell;
+	Relation	rel = NULL;
+
+	/*
+	 * Examine the FROM clause.  Currently, we only allow it to be a single
+	 * simple table, but later we'll probably allow multiple tables and JOIN
+	 * syntax.  The grammar is already prepared for that, so we have to check
+	 * here that what we got is what we can support.
+	 */
+	if (list_length(from_clause) != 1)
+		ereport(ERROR,
+				errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+				errmsg("only a single relation is allowed in CREATE STATISTICS"));
+
+	foreach(cell, from_clause)
+	{
+		Node	   *rln = (Node *) lfirst(cell);
+
+		if (!IsA(rln, 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 only ShareUpdateExclusiveLock on relation,
+		 * conflicting with ANALYZE and other DDL that sets statistical
+		 * information, but not with normal queries.
+		 */
+		rel = relation_openrv((RangeVar *) rln, ShareUpdateExclusiveLock);
+
+		/* Restrict to allowed relation types */
+		if (rel->rd_rel->relkind != RELKIND_RELATION &&
+			rel->rd_rel->relkind != RELKIND_MATVIEW &&
+			rel->rd_rel->relkind != RELKIND_FOREIGN_TABLE &&
+			rel->rd_rel->relkind != RELKIND_PARTITIONED_TABLE)
+			ereport(ERROR,
+					errcode(ERRCODE_WRONG_OBJECT_TYPE),
+					errmsg("cannot define statistics for relation \"%s\"",
+						   RelationGetRelationName(rel)),
+					errdetail_relkind_not_supported(rel->rd_rel->relkind));
+
+		/*
+		 * You must own the relation to create stats on it.
+		 *
+		 * NB: Concurrent changes could cause this function's lookup to find a
+		 * different relation than a previous lookup by the caller, so we must
+		 * perform this check unconditionally.
+		 */
+		if (!object_ownercheck(RelationRelationId, RelationGetRelid(rel), GetUserId()))
+			aclcheck_error(ACLCHECK_NOT_OWNER, get_relkind_objtype(rel->rd_rel->relkind),
+						   RelationGetRelationName(rel));
+
+		/* Creating statistics on system catalogs is not allowed */
+		if (!allowSystemTableMods && IsSystemRelation(rel))
+			ereport(ERROR,
+					errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
+					errmsg("permission denied: \"%s\" is a system catalog",
+						   RelationGetRelationName(rel)));
+	}
+
+	/* Create a range table entry. */
+	rte = makeNode(RangeTblEntry);
+	rte->rtekind = RTE_RELATION;
+	rte->relid = RelationGetRelid(rel);
+	rte->rellockmode = ShareUpdateExclusiveLock;
+
+	/* Close relation */
+	relation_close(rel, NoLock);
+
+	return list_make1(rte);
+}
+
 
 /*
  * transformRuleStmt -
diff --git a/src/backend/tcop/utility.c b/src/backend/tcop/utility.c
index d18a3a60a46..0c31113ebb5 100644
--- a/src/backend/tcop/utility.c
+++ b/src/backend/tcop/utility.c
@@ -1874,34 +1874,7 @@ 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, true);
-				}
+				address = CreateStatistics((CreateStatsStmt *) parsetree, true, queryString);
 				break;
 
 			case T_AlterStatsStmt:
diff --git a/src/include/commands/defrem.h b/src/include/commands/defrem.h
index f3432b4b6a1..95397f91c5a 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, bool check_rights);
+extern ObjectAddress CreateStatistics(CreateStatsStmt *stmt, bool check_rights, 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/nodes/parsenodes.h b/src/include/nodes/parsenodes.h
index bc7adba4a0f..326d30cfb2f 100644
--- a/src/include/nodes/parsenodes.h
+++ b/src/include/nodes/parsenodes.h
@@ -3551,6 +3551,10 @@ typedef struct CreateStatsStmt
 	List	   *stat_types;		/* stat types (list of String) */
 	List	   *exprs;			/* expressions to build statistics on */
 	List	   *relations;		/* rels to build stats on (list of RangeVar) */
+	List	   *from_clause;	/* FROM clause ((list of RangeVar)) */
+	List	   *rtable;			/* It’s not derived directly from the
+								 * parser, instead it comes from parse
+								 * analysis. (list of RangeTblEntry) */
 	char	   *stxcomment;		/* comment to apply to stats, or NULL */
 	bool		transformed;	/* true when transformStatsStmt is finished */
 	bool		if_not_exists;	/* do nothing if stats name already exists */
diff --git a/src/include/parser/parse_utilcmd.h b/src/include/parser/parse_utilcmd.h
index 4965fac4495..499e9ebef1c 100644
--- a/src/include/parser/parse_utilcmd.h
+++ b/src/include/parser/parse_utilcmd.h
@@ -26,8 +26,9 @@ 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(CreateStatsStmt *stmt,
 										   const char *queryString);
+extern List *transformStatsFromClause(List *from_clause);
 extern void transformRuleStmt(RuleStmt *stmt, const char *queryString,
 							  List **actions, Node **whereClause);
 extern List *transformCreateSchemaStmtElements(List *schemaElts,
-- 
2.34.1