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Re: extension patch of CREATE OR REPLACE TRIGGER
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* Re: extension patch of CREATE OR REPLACE TRIGGER
@ 2019-12-01 03:36 Michael Paquier <[email protected]>
  2019-12-02 01:56 ` RE: extension patch of CREATE OR REPLACE TRIGGER [email protected] <[email protected]>
  0 siblings, 1 reply; 265+ messages in thread

From: Michael Paquier @ 2019-12-01 03:36 UTC (permalink / raw)
  To: Thomas Munro <[email protected]>; +Cc: Tom Lane <[email protected]>; [email protected] <[email protected]>; Surafel Temesgen <[email protected]>; pgsql-hackers

On Thu, Aug 01, 2019 at 09:49:53PM +1200, Thomas Munro wrote:
> The end of CF1 is here.  I've moved this patch to CF2 (September) in
> the Commitfest app.  Of course, everyone is free to continue
> discussing the patch before then.  When you have a new version, please
> set the status to "Needs review".

The latest patch includes calls to heap_open(), causing its
compilation to fail.  Could you please send a rebased version of the
patch?  I have moved the entry to next CF, waiting on author.
--
Michael


Attachments:

  [application/pgp-signature] signature.asc (833B, ../../[email protected]/2-signature.asc)
  download

^ permalink  raw  reply  [nested|flat] 265+ messages in thread

* RE: extension patch of CREATE OR REPLACE TRIGGER
  2019-12-01 03:36 Re: extension patch of CREATE OR REPLACE TRIGGER Michael Paquier <[email protected]>
@ 2019-12-02 01:56 ` [email protected] <[email protected]>
  0 siblings, 0 replies; 265+ messages in thread

From: [email protected] @ 2019-12-02 01:56 UTC (permalink / raw)
  To: 'Michael Paquier' <[email protected]>; Thomas Munro <[email protected]>; +Cc: Tom Lane <[email protected]>; Surafel Temesgen <[email protected]>; pgsql-hackers

Dear Michael san

> The latest patch includes calls to heap_open(), causing its compilation to fail.
> Could you please send a rebased version of the patch?  I have moved the entry to
> next CF, waiting on author.
Thanks. I've fixed where you pointed out. 
Also, I'm waiting for other kind of feedbacks from anyone.

Regards,
	Osumi Takamichi


Attachments:

  [application/octet-stream] CREATE_OR_REPLACE_TRIGGER_v05.patch (21.5K, ../../OSAPR01MB4482A938789C82A1A8C17582ED430@OSAPR01MB4482.jpnprd01.prod.outlook.com/2-CREATE_OR_REPLACE_TRIGGER_v05.patch)
  download | inline diff:
diff --git a/doc/src/sgml/ref/create_trigger.sgml b/doc/src/sgml/ref/create_trigger.sgml
index 3339a4b..65aeea3 100644
--- a/doc/src/sgml/ref/create_trigger.sgml
+++ b/doc/src/sgml/ref/create_trigger.sgml
@@ -26,7 +26,7 @@ PostgreSQL documentation
 
  <refsynopsisdiv>
 <synopsis>
-CREATE [ CONSTRAINT ] TRIGGER <replaceable class="parameter">name</replaceable> { BEFORE | AFTER | INSTEAD OF } { <replaceable class="parameter">event</replaceable> [ OR ... ] }
+CREATE [ OR REPLACE ] [ CONSTRAINT ] TRIGGER <replaceable class="parameter">name</replaceable> { BEFORE | AFTER | INSTEAD OF } { <replaceable class="parameter">event</replaceable> [ OR ... ] }
     ON <replaceable class="parameter">table_name</replaceable>
     [ FROM <replaceable class="parameter">referenced_table_name</replaceable> ]
     [ NOT DEFERRABLE | [ DEFERRABLE ] [ INITIALLY IMMEDIATE | INITIALLY DEFERRED ] ]
diff --git a/src/backend/catalog/heap.c b/src/backend/catalog/heap.c
index b7bcdd9..e742354 100644
--- a/src/backend/catalog/heap.c
+++ b/src/backend/catalog/heap.c
@@ -2371,7 +2371,8 @@ StoreRelCheck(Relation rel, const char *ccname, Node *expr,
 	 * Create the Check Constraint
 	 */
 	constrOid =
-		CreateConstraintEntry(ccname,	/* Constraint Name */
+		CreateConstraintEntry(InvalidOid,
+							  ccname,	/* Constraint Name */
 							  RelationGetNamespace(rel),	/* namespace */
 							  CONSTRAINT_CHECK, /* Constraint Type */
 							  false,	/* Is Deferrable */
diff --git a/src/backend/catalog/index.c b/src/backend/catalog/index.c
index 67f637d..f247cbc 100644
--- a/src/backend/catalog/index.c
+++ b/src/backend/catalog/index.c
@@ -1855,7 +1855,8 @@ index_constraint_create(Relation heapRelation,
 	/*
 	 * Construct a pg_constraint entry.
 	 */
-	conOid = CreateConstraintEntry(constraintName,
+	conOid = CreateConstraintEntry(InvalidOid,
+								   constraintName,
 								   namespaceId,
 								   constraintType,
 								   deferrable,
diff --git a/src/backend/catalog/pg_constraint.c b/src/backend/catalog/pg_constraint.c
index 56568b0..06a2ead 100644
--- a/src/backend/catalog/pg_constraint.c
+++ b/src/backend/catalog/pg_constraint.c
@@ -45,10 +45,12 @@
  * constraint) are *not* created here.  But we do make dependency links
  * from the constraint to the things it depends on.
  *
- * The new constraint's OID is returned.
+ * The new constraint's OID is returned. (This will be the same as
+ * "conOid" if that is specified as nonzero.)
  */
 Oid
-CreateConstraintEntry(const char *constraintName,
+CreateConstraintEntry(Oid existing_constraint_oid,
+					  const char *constraintName,
 					  Oid constraintNamespace,
 					  char constraintType,
 					  bool isDeferrable,
@@ -79,7 +81,7 @@ CreateConstraintEntry(const char *constraintName,
 					  bool is_internal)
 {
 	Relation	conDesc;
-	Oid			conOid;
+	Oid			conOid = InvalidOid;
 	HeapTuple	tup;
 	bool		nulls[Natts_pg_constraint];
 	Datum		values[Natts_pg_constraint];
@@ -92,7 +94,12 @@ CreateConstraintEntry(const char *constraintName,
 	NameData	cname;
 	int			i;
 	ObjectAddress conobject;
-
+	SysScanDesc   conscan;
+	ScanKeyData   skey[2];
+	HeapTuple     tuple;
+	bool          replaces[Natts_pg_constraint];
+	Form_pg_constraint constrForm;
+	
 	conDesc = table_open(ConstraintRelationId, RowExclusiveLock);
 
 	Assert(constraintName);
@@ -164,9 +171,12 @@ CreateConstraintEntry(const char *constraintName,
 		values[i] = (Datum) NULL;
 	}
 
-	conOid = GetNewOidWithIndex(conDesc, ConstraintOidIndexId,
-								Anum_pg_constraint_oid);
-	values[Anum_pg_constraint_oid - 1] = ObjectIdGetDatum(conOid);
+	if (!existing_constraint_oid)
+	{
+		conOid = GetNewOidWithIndex(conDesc, ConstraintOidIndexId,
+									Anum_pg_constraint_oid);
+		values[Anum_pg_constraint_oid - 1] = ObjectIdGetDatum(conOid);
+	}
 	values[Anum_pg_constraint_conname - 1] = NameGetDatum(&cname);
 	values[Anum_pg_constraint_connamespace - 1] = ObjectIdGetDatum(constraintNamespace);
 	values[Anum_pg_constraint_contype - 1] = CharGetDatum(constraintType);
@@ -220,9 +230,47 @@ CreateConstraintEntry(const char *constraintName,
 	else
 		nulls[Anum_pg_constraint_conbin - 1] = true;
 
-	tup = heap_form_tuple(RelationGetDescr(conDesc), values, nulls);
+	if (OidIsValid(existing_constraint_oid))
+	{
+		ScanKeyInit(&skey[0],
+					Anum_pg_constraint_oid,
+					BTEqualStrategyNumber, F_OIDEQ,
+					ObjectIdGetDatum(existing_constraint_oid));
+
+		conscan = systable_beginscan(conDesc,
+						 ConstraintOidIndexId,
+						 true,
+						 NULL,
+						 1,
+						 skey);
+
+		tuple = systable_getnext(conscan);
+		Assert (HeapTupleIsValid(tuple));
+		constrForm = (Form_pg_constraint) GETSTRUCT(tuple);
+		conOid = constrForm->oid;
+		Assert(conOid == existing_constraint_oid);
+
+		memset(replaces, true, sizeof(replaces));
+		replaces[Anum_pg_constraint_oid - 1] = false; /* skip updating Oid data */
+		replaces[Anum_pg_constraint_conname - 1] = false;
+		replaces[Anum_pg_constraint_confrelid - 1] = false;
+
+		/* Modify the existing constraint entry */
+		tup = heap_modify_tuple(tuple, RelationGetDescr(conDesc), values, nulls, replaces);
+		CatalogTupleUpdate(conDesc, &tuple->t_self, tup);
+		heap_freetuple(tup);
 
-	CatalogTupleInsert(conDesc, tup);
+		/* Remove all old dependencies before registering new ones */
+		deleteDependencyRecordsFor(ConstraintRelationId, conOid, true);
+
+		systable_endscan(conscan);
+	}
+	else
+	{
+		tup = heap_form_tuple(RelationGetDescr(conDesc), values, nulls);
+		CatalogTupleInsert(conDesc, tup);
+		heap_freetuple(tup);
+	}
 
 	conobject.classId = ConstraintRelationId;
 	conobject.objectId = conOid;
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index 5440eb9..6890606 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -8125,7 +8125,8 @@ addFkRecurseReferenced(List **wqueue, Constraint *fkconstraint, Relation rel,
 	/*
 	 * Record the FK constraint in pg_constraint.
 	 */
-	constrOid = CreateConstraintEntry(conname,
+	constrOid = CreateConstraintEntry(InvalidOid,
+									  conname,
 									  RelationGetNamespace(rel),
 									  CONSTRAINT_FOREIGN,
 									  fkconstraint->deferrable,
@@ -8153,7 +8154,7 @@ addFkRecurseReferenced(List **wqueue, Constraint *fkconstraint, Relation rel,
 									  conislocal,	/* islocal */
 									  coninhcount,	/* inhcount */
 									  connoinherit, /* conNoInherit */
-									  false);	/* is_internal */
+									  false); /* is_internal */
 
 	ObjectAddressSet(address, ConstraintRelationId, constrOid);
 
@@ -8393,7 +8394,8 @@ addFkRecurseReferencing(List **wqueue, Constraint *fkconstraint, Relation rel,
 			else
 				conname = fkconstraint->conname;
 			constrOid =
-				CreateConstraintEntry(conname,
+				CreateConstraintEntry(InvalidOid,
+									  conname,
 									  RelationGetNamespace(partition),
 									  CONSTRAINT_FOREIGN,
 									  fkconstraint->deferrable,
@@ -8788,7 +8790,8 @@ CloneFkReferencing(List **wqueue, Relation parentRel, Relation partRel)
 
 		indexOid = constrForm->conindid;
 		constrOid =
-			CreateConstraintEntry(fkconstraint->conname,
+			CreateConstraintEntry(InvalidOid,
+								  fkconstraint->conname,
 								  constrForm->connamespace,
 								  CONSTRAINT_FOREIGN,
 								  fkconstraint->deferrable,
diff --git a/src/backend/commands/trigger.c b/src/backend/commands/trigger.c
index 8d22d43..8ed3ff3 100644
--- a/src/backend/commands/trigger.c
+++ b/src/backend/commands/trigger.c
@@ -31,6 +31,7 @@
 #include "catalog/pg_proc.h"
 #include "catalog/pg_trigger.h"
 #include "catalog/pg_type.h"
+#include "catalog/pg_depend.h"
 #include "commands/dbcommands.h"
 #include "commands/defrem.h"
 #include "commands/trigger.h"
@@ -180,7 +181,7 @@ CreateTrigger(CreateTrigStmt *stmt, const char *queryString,
 	Relation	pgrel;
 	HeapTuple	tuple;
 	Oid			funcrettype;
-	Oid			trigoid;
+	Oid			trigoid = InvalidOid;
 	char		internaltrigname[NAMEDATALEN];
 	char	   *trigname;
 	Oid			constrrelid = InvalidOid;
@@ -189,6 +190,12 @@ CreateTrigger(CreateTrigStmt *stmt, const char *queryString,
 	char	   *oldtablename = NULL;
 	char	   *newtablename = NULL;
 	bool		partition_recurse;
+	bool		is_update = false;
+	HeapTuple	newtup;
+	TupleDesc	tupDesc;
+	bool		replaces[Natts_pg_trigger];
+	Oid		existing_constraint_oid = InvalidOid;
+	bool		trigger_exists = false;
 
 	if (OidIsValid(relOid))
 		rel = table_open(relOid, ShareRowExclusiveLock);
@@ -685,6 +692,61 @@ CreateTrigger(CreateTrigStmt *stmt, const char *queryString,
 		whenRtable = NIL;
 	}
 
+	/* See if there is a pre-existing trigger of the same name */
+	tgrel = table_open(TriggerRelationId, RowExclusiveLock);
+
+	ScanKeyInit(&key,
+			Anum_pg_trigger_tgrelid,
+			BTEqualStrategyNumber, F_OIDEQ,
+			ObjectIdGetDatum(RelationGetRelid(rel)));
+	tgscan = systable_beginscan(tgrel, TriggerRelidNameIndexId, true,
+								NULL, 1, &key);
+	while (HeapTupleIsValid(tuple = systable_getnext(tgscan)))
+	{
+		Form_pg_trigger pg_trigger = (Form_pg_trigger) GETSTRUCT(tuple);
+
+		if (namestrcmp(&(pg_trigger->tgname), stmt->trigname) == 0)
+		{
+			trigoid = pg_trigger->oid;
+			existing_constraint_oid = pg_trigger->tgconstraint;
+			trigger_exists = true;
+			break;
+		}
+	}
+	systable_endscan(tgscan);
+
+	/* Generate the trigger's oid because there was no same name trigger. */
+	if (!trigger_exists)
+		trigoid = GetNewOidWithIndex(tgrel, TriggerOidIndexId,
+									 Anum_pg_trigger_oid);
+	else
+	{
+		/*
+		 * without OR REPLACE clause, can't override the trigger with the same name.
+		 */
+		if (!stmt->replace && !isInternal)
+			ereport(ERROR,
+					(errcode(ERRCODE_DUPLICATE_OBJECT),
+					 errmsg("trigger \"%s\" for relation \"%s\" already exists",
+							stmt->trigname, RelationGetRelationName(rel))));
+		/*
+		 * CREATE OR REPLACE CONSTRAINT TRIGGER command can't replace non-constraint trigger.
+		 */
+		if (stmt->replace && stmt->isconstraint && !OidIsValid(existing_constraint_oid))
+			ereport(ERROR,
+					(errcode(ERRCODE_DUPLICATE_OBJECT),
+					 errmsg("Trigger \"%s\" for relation \"%s\" cannot be replaced with constraint trigger",
+							stmt->trigname, RelationGetRelationName(rel))));
+		/*
+		 * CREATE OR REPLACE TRIGGER command can't replace constraint trigger.
+		 */
+		if (stmt->replace && !stmt->isconstraint && OidIsValid(existing_constraint_oid))
+			ereport(ERROR,
+					(errcode(ERRCODE_DUPLICATE_OBJECT),
+					 errmsg("Constraint trigger \"%s\" for relation \"%s\" cannot be replaced with non-constraint trigger",
+							stmt->trigname, RelationGetRelationName(rel))));
+	}
+
 	/*
 	 * Find and validate the trigger function.
 	 */
@@ -747,7 +809,8 @@ CreateTrigger(CreateTrigStmt *stmt, const char *queryString,
 	{
 		/* Internal callers should have made their own constraints */
 		Assert(!isInternal);
-		constraintOid = CreateConstraintEntry(stmt->trigname,
+		constraintOid = CreateConstraintEntry(existing_constraint_oid,
+											  stmt->trigname,
 											  RelationGetNamespace(rel),
 											  CONSTRAINT_TRIGGER,
 											  stmt->deferrable,
@@ -779,15 +842,6 @@ CreateTrigger(CreateTrigStmt *stmt, const char *queryString,
 	}
 
 	/*
-	 * Generate the trigger's OID now, so that we can use it in the name if
-	 * needed.
-	 */
-	tgrel = table_open(TriggerRelationId, RowExclusiveLock);
-
-	trigoid = GetNewOidWithIndex(tgrel, TriggerOidIndexId,
-								 Anum_pg_trigger_oid);
-
-	/*
 	 * If trigger is internally generated, modify the provided trigger name to
 	 * ensure uniqueness by appending the trigger OID.  (Callers will usually
 	 * supply a simple constant trigger name in these cases.)
@@ -805,37 +859,6 @@ CreateTrigger(CreateTrigStmt *stmt, const char *queryString,
 	}
 
 	/*
-	 * Scan pg_trigger for existing triggers on relation.  We do this only to
-	 * give a nice error message if there's already a trigger of the same
-	 * name.  (The unique index on tgrelid/tgname would complain anyway.) We
-	 * can skip this for internally generated triggers, since the name
-	 * modification above should be sufficient.
-	 *
-	 * NOTE that this is cool only because we have ShareRowExclusiveLock on
-	 * the relation, so the trigger set won't be changing underneath us.
-	 */
-	if (!isInternal)
-	{
-		ScanKeyInit(&key,
-					Anum_pg_trigger_tgrelid,
-					BTEqualStrategyNumber, F_OIDEQ,
-					ObjectIdGetDatum(RelationGetRelid(rel)));
-		tgscan = systable_beginscan(tgrel, TriggerRelidNameIndexId, true,
-									NULL, 1, &key);
-		while (HeapTupleIsValid(tuple = systable_getnext(tgscan)))
-		{
-			Form_pg_trigger pg_trigger = (Form_pg_trigger) GETSTRUCT(tuple);
-
-			if (namestrcmp(&(pg_trigger->tgname), trigname) == 0)
-				ereport(ERROR,
-						(errcode(ERRCODE_DUPLICATE_OBJECT),
-						 errmsg("trigger \"%s\" for relation \"%s\" already exists",
-								trigname, RelationGetRelationName(rel))));
-		}
-		systable_endscan(tgscan);
-	}
-
-	/*
 	 * Build the new pg_trigger tuple.
 	 *
 	 * When we're creating a trigger in a partition, we mark it as internal,
@@ -962,12 +985,51 @@ CreateTrigger(CreateTrigStmt *stmt, const char *queryString,
 
 	tuple = heap_form_tuple(tgrel->rd_att, values, nulls);
 
-	/*
-	 * Insert tuple into pg_trigger.
-	 */
-	CatalogTupleInsert(tgrel, tuple);
+	if (!trigger_exists)
+	{
+		tuple = heap_form_tuple(tgrel->rd_att, values, nulls);
+
+		/*
+		 * Insert tuple into pg_trigger.
+		 */
+		CatalogTupleInsert(tgrel, tuple);
+
+		heap_freetuple(tuple);
+	}
+	else
+	{
+		memset(replaces, true, sizeof(replaces));
+
+		ScanKeyInit(&key,
+				Anum_pg_trigger_tgrelid,
+				BTEqualStrategyNumber, F_OIDEQ,
+				ObjectIdGetDatum(RelationGetRelid(rel)));
+		tgscan = systable_beginscan(tgrel, TriggerRelidNameIndexId, true,
+									NULL, 1, &key);
+		while (HeapTupleIsValid(tuple = systable_getnext(tgscan)))
+		{
+			Form_pg_trigger pg_trigger = (Form_pg_trigger) GETSTRUCT(tuple);
+
+			if (namestrcmp(&(pg_trigger->tgname), trigname) == 0)
+			{
+				tupDesc = RelationGetDescr(tgrel);
+				replaces[Anum_pg_trigger_oid - 1] = false; /* skip updating Oid data */
+				replaces[Anum_pg_trigger_tgrelid - 1] = false;
+				replaces[Anum_pg_trigger_tgname - 1] = false;
+				trigoid = pg_trigger->oid;
+				newtup = heap_modify_tuple(tuple, tupDesc, values, nulls, replaces);
+
+				/* Update tuple in pg_trigger */
+				CatalogTupleUpdate(tgrel, &tuple->t_self, newtup);
+
+				heap_freetuple(newtup);
+				is_update = true;
+				break;
+			}
+		}
+		systable_endscan(tgscan);
+	}
 
-	heap_freetuple(tuple);
 	table_close(tgrel, RowExclusiveLock);
 
 	pfree(DatumGetPointer(values[Anum_pg_trigger_tgname - 1]));
@@ -1010,6 +1072,15 @@ CreateTrigger(CreateTrigStmt *stmt, const char *queryString,
 	myself.objectId = trigoid;
 	myself.objectSubId = 0;
 
+	/*
+	 * In case of replace trigger, trigger should no-more dependent on old
+	 * referenced objects. Always remove the old dependencies and then
+	 * register new ones. In that way, even if the old referenced object gets
+	 * dropped, trigger will remain in the database.
+	 */
+	if (is_update)
+		deleteDependencyRecordsFor(myself.classId, myself.objectId, true);
+
 	referenced.classId = ProcedureRelationId;
 	referenced.objectId = funcoid;
 	referenced.objectSubId = 0;
diff --git a/src/backend/commands/typecmds.c b/src/backend/commands/typecmds.c
index 89887b8..a6e3619 100644
--- a/src/backend/commands/typecmds.c
+++ b/src/backend/commands/typecmds.c
@@ -3146,7 +3146,8 @@ domainAddConstraint(Oid domainOid, Oid domainNamespace, Oid baseTypeOid,
 	 * Store the constraint in pg_constraint
 	 */
 	ccoid =
-		CreateConstraintEntry(constr->conname,	/* Constraint Name */
+		CreateConstraintEntry(InvalidOid,
+							  constr->conname,	/* Constraint Name */
 							  domainNamespace,	/* namespace */
 							  CONSTRAINT_CHECK, /* Constraint Type */
 							  false,	/* Is Deferrable */
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index c508684..d0e8108 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -5353,48 +5353,50 @@ am_type:
  *****************************************************************************/
 
 CreateTrigStmt:
-			CREATE TRIGGER name TriggerActionTime TriggerEvents ON
+			CREATE opt_or_replace TRIGGER name TriggerActionTime TriggerEvents ON
 			qualified_name TriggerReferencing TriggerForSpec TriggerWhen
 			EXECUTE FUNCTION_or_PROCEDURE func_name '(' TriggerFuncArgs ')'
 				{
 					CreateTrigStmt *n = makeNode(CreateTrigStmt);
-					n->trigname = $3;
-					n->relation = $7;
-					n->funcname = $13;
-					n->args = $15;
-					n->row = $9;
-					n->timing = $4;
-					n->events = intVal(linitial($5));
-					n->columns = (List *) lsecond($5);
-					n->whenClause = $10;
-					n->transitionRels = $8;
+					n->replace = $2;
+					n->trigname = $4;
+					n->relation = $8;
+					n->funcname = $14;
+					n->args = $16;
+					n->row = $10;
+					n->timing = $5;
+					n->events = intVal(linitial($6));
+					n->columns = (List *) lsecond($6);
+					n->whenClause = $11;
+					n->transitionRels = $9;
 					n->isconstraint  = false;
 					n->deferrable	 = false;
 					n->initdeferred  = false;
 					n->constrrel = NULL;
 					$$ = (Node *)n;
 				}
-			| CREATE CONSTRAINT TRIGGER name AFTER TriggerEvents ON
+			| CREATE opt_or_replace CONSTRAINT TRIGGER name AFTER TriggerEvents ON
 			qualified_name OptConstrFromTable ConstraintAttributeSpec
 			FOR EACH ROW TriggerWhen
 			EXECUTE FUNCTION_or_PROCEDURE func_name '(' TriggerFuncArgs ')'
 				{
 					CreateTrigStmt *n = makeNode(CreateTrigStmt);
-					n->trigname = $4;
-					n->relation = $8;
-					n->funcname = $17;
-					n->args = $19;
+					n->replace = $2;
+					n->trigname = $5;
+					n->relation = $9;
+					n->funcname = $18;
+					n->args = $20;
 					n->row = true;
 					n->timing = TRIGGER_TYPE_AFTER;
-					n->events = intVal(linitial($6));
-					n->columns = (List *) lsecond($6);
-					n->whenClause = $14;
+					n->events = intVal(linitial($7));
+					n->columns = (List *) lsecond($7);
+					n->whenClause = $15;
 					n->transitionRels = NIL;
 					n->isconstraint  = true;
-					processCASbits($10, @10, "TRIGGER",
+					processCASbits($11, @11, "TRIGGER",
 								   &n->deferrable, &n->initdeferred, NULL,
 								   NULL, yyscanner);
-					n->constrrel = $9;
+					n->constrrel = $10;
 					$$ = (Node *)n;
 				}
 		;
diff --git a/src/include/catalog/pg_constraint.h b/src/include/catalog/pg_constraint.h
index cbb5d9a..b6531e9 100644
--- a/src/include/catalog/pg_constraint.h
+++ b/src/include/catalog/pg_constraint.h
@@ -182,7 +182,8 @@ typedef enum ConstraintCategory
 } ConstraintCategory;
 
 
-extern Oid	CreateConstraintEntry(const char *constraintName,
+extern Oid	CreateConstraintEntry(Oid existing_constraint_oid,
+								  const char *constraintName,
 								  Oid constraintNamespace,
 								  char constraintType,
 								  bool isDeferrable,
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h
index ff626cb..29349c7 100644
--- a/src/include/nodes/parsenodes.h
+++ b/src/include/nodes/parsenodes.h
@@ -2418,6 +2418,7 @@ typedef struct CreateTrigStmt
 	bool		isconstraint;	/* This is a constraint trigger */
 	/* explicitly named transition data */
 	List	   *transitionRels; /* TriggerTransition nodes, or NIL if none */
+	bool		replace;		/* T => replace if already exists */
 	/* The remaining fields are only used for constraint triggers */
 	bool		deferrable;		/* [NOT] DEFERRABLE */
 	bool		initdeferred;	/* INITIALLY {DEFERRED|IMMEDIATE} */
diff --git a/src/test/regress/expected/triggers.out b/src/test/regress/expected/triggers.out
index 1e4053c..ff3a7b1 100644
--- a/src/test/regress/expected/triggers.out
+++ b/src/test/regress/expected/triggers.out
@@ -2918,3 +2918,27 @@ drop table self_ref;
 drop function dump_insert();
 drop function dump_update();
 drop function dump_delete();
+-- 
+-- Test case for CREATE OR REPLACE TRIGGER
+--
+create table my_table (id integer);
+create function before_replacement() returns trigger as $$
+begin
+raise notice 'function replaced by another function';
+return null;
+end; $$ language plpgsql;
+create function after_replacement() returns trigger as $$
+begin
+raise notice 'function to replace the initial function';
+return null;
+end; $$ language plpgsql;
+create or replace trigger my_trig before insert on my_table for each row execute procedure before_replacement();
+insert into my_table (id) values (1);
+NOTICE:  function replaced by another function
+create or replace trigger my_trig before insert on my_table for each row execute procedure after_replacement();
+insert into my_table (id) values (2);
+NOTICE:  function to replace the initial function
+drop trigger my_trig on my_table;
+drop function before_replacement();
+drop function after_replacement();
+drop table my_table;
diff --git a/src/test/regress/sql/triggers.sql b/src/test/regress/sql/triggers.sql
index c21b6c1..6ab5cfb 100644
--- a/src/test/regress/sql/triggers.sql
+++ b/src/test/regress/sql/triggers.sql
@@ -2209,3 +2209,30 @@ drop table self_ref;
 drop function dump_insert();
 drop function dump_update();
 drop function dump_delete();
+
+-- 
+-- Test case for CREATE OR REPLACE TRIGGER
+--
+create table my_table (id integer);
+create function before_replacement() returns trigger as $$
+begin
+raise notice 'function replaced by another function';
+return null;
+end; $$ language plpgsql;
+
+create function after_replacement() returns trigger as $$
+begin
+raise notice 'function to replace the initial function';
+return null;
+end; $$ language plpgsql;
+
+create or replace trigger my_trig before insert on my_table for each row execute procedure before_replacement();
+insert into my_table (id) values (1);
+
+create or replace trigger my_trig before insert on my_table for each row execute procedure after_replacement();
+insert into my_table (id) values (2);
+
+drop trigger my_trig on my_table;
+drop function before_replacement();
+drop function after_replacement();
+drop table my_table;


^ permalink  raw  reply  [nested|flat] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread

* [PATCH v4] Restructure CreateStatsStmt parse-analysis processing
@ 2025-10-17 11:55 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 265+ 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] 265+ messages in thread