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ECPG parse.pl and parse2.pl
266+ messages / 4 participants
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* ECPG parse.pl and parse2.pl
@ 2011-06-13 19:59  Peter Eisentraut <[email protected]>
  0 siblings, 2 replies; 266+ messages in thread

From: Peter Eisentraut @ 2011-06-13 19:59 UTC (permalink / raw)
  To: pgsql-hackers

Surely we don't need parse.pl and parse2.pl?  parse.pl, the one that's
not used, it already showing signs of semi-bit-rot:

Use of assignment to $[ is deprecated at ./parse.pl line 21.

I propose that we move parse2.pl to parse.pl and only keep the one.





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* Re: ECPG parse.pl and parse2.pl
@ 2011-06-13 20:20  Tom Lane <[email protected]>
  parent: Peter Eisentraut <[email protected]>
  1 sibling, 0 replies; 266+ messages in thread

From: Tom Lane @ 2011-06-13 20:20 UTC (permalink / raw)
  To: Peter Eisentraut <[email protected]>; +Cc: pgsql-hackers

Peter Eisentraut <[email protected]> writes:
> Surely we don't need parse.pl and parse2.pl?  parse.pl, the one that's
> not used, it already showing signs of semi-bit-rot:

> Use of assignment to $[ is deprecated at ./parse.pl line 21.

> I propose that we move parse2.pl to parse.pl and only keep the one.

Yes.  This was objected to immediately when Michael made it that way in
the first place, but he didn't change it.  I don't think we need to use
HEAD as a repository for obsolete code, when we have a perfectly good
SCM.

			regards, tom lane



^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* Re: ECPG parse.pl and parse2.pl
@ 2011-06-14 08:16  Michael Meskes <[email protected]>
  parent: Peter Eisentraut <[email protected]>
  1 sibling, 0 replies; 266+ messages in thread

From: Michael Meskes @ 2011-06-14 08:16 UTC (permalink / raw)
  To: Peter Eisentraut <[email protected]>; +Cc: pgsql-hackers

On Mon, Jun 13, 2011 at 10:59:38PM +0300, Peter Eisentraut wrote:
> I propose that we move parse2.pl to parse.pl and only keep the one.

I agree, thanks for taking care.

Originally I wanted to keep parse.pl around for a bit, so I could run both and
compare the output over the development cycle. But with 9.1 being so close,
there's no need for the old script anymore.

Michael
-- 
Michael Meskes
Michael at Fam-Meskes dot De, Michael at Meskes dot (De|Com|Net|Org)
Michael at BorussiaFan dot De, Meskes at (Debian|Postgresql) dot Org
Jabber: michael.meskes at googlemail dot com
VfL Borussia! Força Barça! Go SF 49ers! Use Debian GNU/Linux, PostgreSQL



^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





^ permalink  raw  reply  [nested|flat] 266+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 266+ messages in thread

From: Álvaro Herrera @ 2025-10-17 11:55 UTC (permalink / raw)

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 <[email protected]>
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


--xzcma6eafn4gmiua--





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