Add a missing_ok argument to get_object_address().

This lays the groundwork for an upcoming patch to streamline the
handling of DROP commands.

KaiGai Kohei

src/backend/catalog/objectaddress.c

@@ -72,15 +72,19 @@
 #include "utils/tqual.h"
 
 static ObjectAddress get_object_address_unqualified(ObjectType objtype,
-							   List *qualname);
-static Relation get_relation_by_qualified_name(ObjectType objtype,
-							   List *objname, LOCKMODE lockmode);
+							   List *qualname, bool missing_ok);
+static ObjectAddress get_relation_by_qualified_name(ObjectType objtype,
+							   List *objname, Relation *relp,
+							   LOCKMODE lockmode, bool missing_ok);
 static ObjectAddress get_object_address_relobject(ObjectType objtype,
-							 List *objname, Relation *relp);
+							 List *objname, Relation *relp, bool missing_ok);
 static ObjectAddress get_object_address_attribute(ObjectType objtype,
-						   List *objname, Relation *relp, LOCKMODE lockmode);
+							 List *objname, Relation *relp,
+							 LOCKMODE lockmode, bool missing_ok);
+static ObjectAddress get_object_address_type(ObjectType objtype,
+						List *objname, bool missing_ok);
 static ObjectAddress get_object_address_opcf(ObjectType objtype, List *objname,
-						List *objargs);
+						List *objargs, bool missing_ok);
 static bool object_exists(ObjectAddress address);
 
 
@@ -106,7 +110,7 @@ static bool object_exists(ObjectAddress address);
  */
 ObjectAddress
 get_object_address(ObjectType objtype, List *objname, List *objargs,
-				   Relation *relp, LOCKMODE lockmode)
+				   Relation *relp, LOCKMODE lockmode, bool missing_ok)
 {
 	ObjectAddress address;
 	Relation	relation = NULL;
@@ -121,21 +125,22 @@ get_object_address(ObjectType objtype, List *objname, List *objargs,
 		case OBJECT_TABLE:
 		case OBJECT_VIEW:
 		case OBJECT_FOREIGN_TABLE:
-			relation =
-				get_relation_by_qualified_name(objtype, objname, lockmode);
-			address.classId = RelationRelationId;
-			address.objectId = RelationGetRelid(relation);
-			address.objectSubId = 0;
+			address =
+				get_relation_by_qualified_name(objtype, objname,
+											   &relation, lockmode,
+											   missing_ok);
 			break;
 		case OBJECT_COLUMN:
 			address =
-				get_object_address_attribute(objtype, objname, &relation,
-											 lockmode);
+				get_object_address_attribute(objtype, objname,
+											 &relation, lockmode,
+											 missing_ok);
 			break;
 		case OBJECT_RULE:
 		case OBJECT_TRIGGER:
 		case OBJECT_CONSTRAINT:
-			address = get_object_address_relobject(objtype, objname, &relation);
+			address = get_object_address_relobject(objtype, objname,
+												   &relation, missing_ok);
 			break;
 		case OBJECT_DATABASE:
 		case OBJECT_EXTENSION:
@@ -145,23 +150,23 @@ get_object_address(ObjectType objtype, List *objname, List *objargs,
 		case OBJECT_LANGUAGE:
 		case OBJECT_FDW:
 		case OBJECT_FOREIGN_SERVER:
-			address = get_object_address_unqualified(objtype, objname);
+			address = get_object_address_unqualified(objtype,
+													 objname, missing_ok);
 			break;
 		case OBJECT_TYPE:
 		case OBJECT_DOMAIN:
-			address.classId = TypeRelationId;
-			address.objectId =
-				typenameTypeId(NULL, makeTypeNameFromNameList(objname));
-			address.objectSubId = 0;
+			address = get_object_address_type(objtype, objname, missing_ok);
 			break;
 		case OBJECT_AGGREGATE:
 			address.classId = ProcedureRelationId;
-			address.objectId = LookupAggNameTypeNames(objname, objargs, false);
+			address.objectId =
+				LookupAggNameTypeNames(objname, objargs, missing_ok);
 			address.objectSubId = 0;
 			break;
 		case OBJECT_FUNCTION:
 			address.classId = ProcedureRelationId;
-			address.objectId = LookupFuncNameTypeNames(objname, objargs, false);
+			address.objectId =
+				LookupFuncNameTypeNames(objname, objargs, missing_ok);
 			address.objectSubId = 0;
 			break;
 		case OBJECT_OPERATOR:
@@ -171,22 +176,23 @@ get_object_address(ObjectType objtype, List *objname, List *objargs,
 				LookupOperNameTypeNames(NULL, objname,
 										(TypeName *) linitial(objargs),
 										(TypeName *) lsecond(objargs),
-										false, -1);
+										missing_ok, -1);
 			address.objectSubId = 0;
 			break;
 		case OBJECT_COLLATION:
 			address.classId = CollationRelationId;
-			address.objectId = get_collation_oid(objname, false);
+			address.objectId = get_collation_oid(objname, missing_ok);
 			address.objectSubId = 0;
 			break;
 		case OBJECT_CONVERSION:
 			address.classId = ConversionRelationId;
-			address.objectId = get_conversion_oid(objname, false);
+			address.objectId = get_conversion_oid(objname, missing_ok);
 			address.objectSubId = 0;
 			break;
 		case OBJECT_OPCLASS:
 		case OBJECT_OPFAMILY:
-			address = get_object_address_opcf(objtype, objname, objargs);
+			address = get_object_address_opcf(objtype,
+											  objname, objargs, missing_ok);
 			break;
 		case OBJECT_LARGEOBJECT:
 			Assert(list_length(objname) == 1);
@@ -194,10 +200,13 @@ get_object_address(ObjectType objtype, List *objname, List *objargs,
 			address.objectId = oidparse(linitial(objname));
 			address.objectSubId = 0;
 			if (!LargeObjectExists(address.objectId))
+			{
+				if (!missing_ok)
 				ereport(ERROR,
 						(errcode(ERRCODE_UNDEFINED_OBJECT),
 						 errmsg("large object %u does not exist",
 								address.objectId)));
+			}
 			break;
 		case OBJECT_CAST:
 			{
@@ -208,28 +217,28 @@ get_object_address(ObjectType objtype, List *objname, List *objargs,
 
 				address.classId = CastRelationId;
 				address.objectId =
-					get_cast_oid(sourcetypeid, targettypeid, false);
+					get_cast_oid(sourcetypeid, targettypeid, missing_ok);
 				address.objectSubId = 0;
 			}
 			break;
 		case OBJECT_TSPARSER:
 			address.classId = TSParserRelationId;
-			address.objectId = get_ts_parser_oid(objname, false);
+			address.objectId = get_ts_parser_oid(objname, missing_ok);
 			address.objectSubId = 0;
 			break;
 		case OBJECT_TSDICTIONARY:
 			address.classId = TSDictionaryRelationId;
-			address.objectId = get_ts_dict_oid(objname, false);
+			address.objectId = get_ts_dict_oid(objname, missing_ok);
 			address.objectSubId = 0;
 			break;
 		case OBJECT_TSTEMPLATE:
 			address.classId = TSTemplateRelationId;
-			address.objectId = get_ts_template_oid(objname, false);
+			address.objectId = get_ts_template_oid(objname, missing_ok);
 			address.objectSubId = 0;
 			break;
 		case OBJECT_TSCONFIGURATION:
 			address.classId = TSConfigRelationId;
-			address.objectId = get_ts_config_oid(objname, false);
+			address.objectId = get_ts_config_oid(objname, missing_ok);
 			address.objectSubId = 0;
 			break;
 		default:
@@ -240,6 +249,15 @@ get_object_address(ObjectType objtype, List *objname, List *objargs,
 			address.objectSubId = 0;
 	}
 
+	/*
+	 * If we could not find the supplied object, return without locking.
+	 */
+	if (!OidIsValid(address.objectId))
+	{
+		Assert(missing_ok);
+		return address;
+	}
+
 	/*
 	 * If we're dealing with a relation or attribute, then the relation is
 	 * already locked.	If we're dealing with any other type of object, we
@@ -267,7 +285,8 @@ get_object_address(ObjectType objtype, List *objname, List *objargs,
  * unqualified name.
  */
 static ObjectAddress
-get_object_address_unqualified(ObjectType objtype, List *qualname)
+get_object_address_unqualified(ObjectType objtype,
+							   List *qualname, bool missing_ok)
 {
 	const char *name;
 	ObjectAddress address;
@@ -323,42 +342,42 @@ get_object_address_unqualified(ObjectType objtype, List *qualname)
 	{
 		case OBJECT_DATABASE:
 			address.classId = DatabaseRelationId;
-			address.objectId = get_database_oid(name, false);
+			address.objectId = get_database_oid(name, missing_ok);
 			address.objectSubId = 0;
 			break;
 		case OBJECT_EXTENSION:
 			address.classId = ExtensionRelationId;
-			address.objectId = get_extension_oid(name, false);
+			address.objectId = get_extension_oid(name, missing_ok);
 			address.objectSubId = 0;
 			break;
 		case OBJECT_TABLESPACE:
 			address.classId = TableSpaceRelationId;
-			address.objectId = get_tablespace_oid(name, false);
+			address.objectId = get_tablespace_oid(name, missing_ok);
 			address.objectSubId = 0;
 			break;
 		case OBJECT_ROLE:
 			address.classId = AuthIdRelationId;
-			address.objectId = get_role_oid(name, false);
+			address.objectId = get_role_oid(name, missing_ok);
 			address.objectSubId = 0;
 			break;
 		case OBJECT_SCHEMA:
 			address.classId = NamespaceRelationId;
-			address.objectId = get_namespace_oid(name, false);
+			address.objectId = get_namespace_oid(name, missing_ok);
 			address.objectSubId = 0;
 			break;
 		case OBJECT_LANGUAGE:
 			address.classId = LanguageRelationId;
-			address.objectId = get_language_oid(name, false);
+			address.objectId = get_language_oid(name, missing_ok);
 			address.objectSubId = 0;
 			break;
 		case OBJECT_FDW:
 			address.classId = ForeignDataWrapperRelationId;
-			address.objectId = get_foreign_data_wrapper_oid(name, false);
+			address.objectId = get_foreign_data_wrapper_oid(name, missing_ok);
 			address.objectSubId = 0;
 			break;
 		case OBJECT_FOREIGN_SERVER:
 			address.classId = ForeignServerRelationId;
-			address.objectId = get_foreign_server_oid(name, false);
+			address.objectId = get_foreign_server_oid(name, missing_ok);
 			address.objectSubId = 0;
 			break;
 		default:
@@ -375,13 +394,23 @@ get_object_address_unqualified(ObjectType objtype, List *qualname)
 /*
  * Locate a relation by qualified name.
  */
-static Relation
+static ObjectAddress
 get_relation_by_qualified_name(ObjectType objtype, List *objname,
-							   LOCKMODE lockmode)
+							   Relation *relp, LOCKMODE lockmode,
+							   bool missing_ok)
 {
 	Relation	relation;
+	ObjectAddress	address;
+
+	address.classId = RelationRelationId;
+	address.objectId = InvalidOid;
+	address.objectSubId = 0;
+
+	relation = relation_openrv_extended(makeRangeVarFromNameList(objname),
+										lockmode, missing_ok);
+	if (!relation)
+		return address;
 
-	relation = relation_openrv(makeRangeVarFromNameList(objname), lockmode);
 	switch (objtype)
 	{
 		case OBJECT_INDEX:
@@ -424,7 +453,11 @@ get_relation_by_qualified_name(ObjectType objtype, List *objname,
 			break;
 	}
 
-	return relation;
+	/* Done */
+	address.objectId = RelationGetRelid(relation);
+	*relp = relation;
+
+	return address;
 }
 
 /*
@@ -435,7 +468,8 @@ get_relation_by_qualified_name(ObjectType objtype, List *objname,
  * mode for the object itself, not the relation to which it is attached.
  */
 static ObjectAddress
-get_object_address_relobject(ObjectType objtype, List *objname, Relation *relp)
+get_object_address_relobject(ObjectType objtype, List *objname,
+							 Relation *relp, bool missing_ok)
 {
 	ObjectAddress address;
 	Relation	relation = NULL;
@@ -461,9 +495,9 @@ get_object_address_relobject(ObjectType objtype, List *objname, Relation *relp)
 		if (objtype != OBJECT_RULE)
 			elog(ERROR, "must specify relation and object name");
 		address.classId = RewriteRelationId;
-		address.objectId = get_rewrite_oid_without_relid(depname, &reloid);
+		address.objectId =
+			get_rewrite_oid_without_relid(depname, &reloid, missing_ok);
 		address.objectSubId = 0;
-		relation = heap_open(reloid, AccessShareLock);
 	}
 	else
 	{
@@ -480,17 +514,18 @@ get_object_address_relobject(ObjectType objtype, List *objname, Relation *relp)
 		{
 			case OBJECT_RULE:
 				address.classId = RewriteRelationId;
-				address.objectId = get_rewrite_oid(reloid, depname, false);
+				address.objectId = get_rewrite_oid(reloid, depname, missing_ok);
 				address.objectSubId = 0;
 				break;
 			case OBJECT_TRIGGER:
 				address.classId = TriggerRelationId;
-				address.objectId = get_trigger_oid(reloid, depname, false);
+				address.objectId = get_trigger_oid(reloid, depname, missing_ok);
 				address.objectSubId = 0;
 				break;
 			case OBJECT_CONSTRAINT:
 				address.classId = ConstraintRelationId;
-				address.objectId = get_constraint_oid(reloid, depname, false);
+				address.objectId =
+					get_constraint_oid(reloid, depname, missing_ok);
 				address.objectSubId = 0;
 				break;
 			default:
@@ -512,13 +547,15 @@ get_object_address_relobject(ObjectType objtype, List *objname, Relation *relp)
  */
 static ObjectAddress
 get_object_address_attribute(ObjectType objtype, List *objname,
-							 Relation *relp, LOCKMODE lockmode)
+							 Relation *relp, LOCKMODE lockmode,
+							 bool missing_ok)
 {
 	ObjectAddress address;
 	List	   *relname;
 	Oid			reloid;
 	Relation	relation;
 	const char *attname;
+	AttrNumber	attnum;
 
 	/* Extract relation name and open relation. */
 	attname = strVal(lfirst(list_tail(objname)));
@@ -527,24 +564,77 @@ get_object_address_attribute(ObjectType objtype, List *objname,
 	reloid = RelationGetRelid(relation);
 
 	/* Look up attribute and construct return value. */
+	attnum = get_attnum(reloid, attname);
+	if (attnum == InvalidAttrNumber)
+	{
+		if (!missing_ok)
+			ereport(ERROR,
+					(errcode(ERRCODE_UNDEFINED_COLUMN),
+					 errmsg("column \"%s\" of relation \"%s\" does not exist",
+							attname, NameListToString(relname))));
+
+		address.classId = RelationRelationId;
+		address.objectId = InvalidOid;
+		address.objectSubId = InvalidAttrNumber;
+		return address;
+	}
+
 	address.classId = RelationRelationId;
 	address.objectId = reloid;
-	address.objectSubId = get_attnum(reloid, attname);
-	if (address.objectSubId == InvalidAttrNumber)
-		ereport(ERROR,
-				(errcode(ERRCODE_UNDEFINED_COLUMN),
-				 errmsg("column \"%s\" of relation \"%s\" does not exist",
-						attname, RelationGetRelationName(relation))));
+	address.objectSubId = attnum;
 
 	*relp = relation;
 	return address;
 }
 
+/*
+ * Find the ObjectAddress for a type or domain
+ */
+static ObjectAddress
+get_object_address_type(ObjectType objtype,
+						List *objname, bool missing_ok)
+{
+	ObjectAddress   address;
+	TypeName   *typename;
+	Type        tup;
+	typename = makeTypeNameFromNameList(objname);
+
+	address.classId = TypeRelationId;
+	address.objectId = InvalidOid;
+	address.objectSubId = 0;
+
+	tup = LookupTypeName(NULL, typename, NULL);
+	if (!HeapTupleIsValid(tup))
+	{
+		if (!missing_ok)
+			ereport(ERROR,
+					(errcode(ERRCODE_UNDEFINED_OBJECT),
+					 errmsg("type \"%s\" does not exist",
+							TypeNameToString(typename))));
+		return address;
+	}
+	address.objectId = typeTypeId(tup);
+
+	if (objtype == OBJECT_DOMAIN)
+	{
+		if (((Form_pg_type) GETSTRUCT(tup))->typtype != TYPTYPE_DOMAIN)
+			ereport(ERROR,
+					(errcode(ERRCODE_WRONG_OBJECT_TYPE),
+					 errmsg("\"%s\" is not a domain",
+							TypeNameToString(typename))));
+	}
+
+	ReleaseSysCache(tup);
+
+	return address;
+}
+
 /*
  * Find the ObjectAddress for an opclass or opfamily.
  */
 static ObjectAddress
-get_object_address_opcf(ObjectType objtype, List *objname, List *objargs)
+get_object_address_opcf(ObjectType objtype,
+						List *objname, List *objargs, bool missing_ok)
 {
 	Oid			amoid;
 	ObjectAddress address;
@@ -556,12 +646,12 @@ get_object_address_opcf(ObjectType objtype, List *objname, List *objargs)
 	{
 		case OBJECT_OPCLASS:
 			address.classId = OperatorClassRelationId;
-			address.objectId = get_opclass_oid(amoid, objname, false);
+			address.objectId = get_opclass_oid(amoid, objname, missing_ok);
 			address.objectSubId = 0;
 			break;
 		case OBJECT_OPFAMILY:
 			address.classId = OperatorFamilyRelationId;
-			address.objectId = get_opfamily_oid(amoid, objname, false);
+			address.objectId = get_opfamily_oid(amoid, objname, missing_ok);
 			address.objectSubId = 0;
 			break;
 		default:

src/backend/commands/comment.c

@@ -69,7 +69,7 @@ CommentObject(CommentStmt *stmt)
 	 * against concurrent DROP operations.
 	 */
 	address = get_object_address(stmt->objtype, stmt->objname, stmt->objargs,
-								 &relation, ShareUpdateExclusiveLock);
+								 &relation, ShareUpdateExclusiveLock, false);
 
 	/* Require ownership of the target object. */
 	check_object_ownership(GetUserId(), stmt->objtype, address,

src/backend/commands/extension.c

@@ -2703,7 +2703,7 @@ ExecAlterExtensionContentsStmt(AlterExtensionContentsStmt *stmt)
 	 * against concurrent DROP and ALTER EXTENSION ADD/DROP operations.
 	 */
 	object = get_object_address(stmt->objtype, stmt->objname, stmt->objargs,
-								&relation, ShareUpdateExclusiveLock);
+								&relation, ShareUpdateExclusiveLock, false);
 
 	/* Permission check: must own target object, too */
 	check_object_ownership(GetUserId(), stmt->objtype, object,

src/backend/commands/seclabel.c

@@ -88,7 +88,7 @@ ExecSecLabelStmt(SecLabelStmt *stmt)
 	 * guard against concurrent modifications.
 	 */
 	address = get_object_address(stmt->objtype, stmt->objname, stmt->objargs,
-								 &relation, ShareUpdateExclusiveLock);
+								 &relation, ShareUpdateExclusiveLock, false);
 
 	/* Require ownership of the target object. */
 	check_object_ownership(GetUserId(), stmt->objtype, address,

src/backend/rewrite/rewriteSupport.c

@@ -132,7 +132,8 @@ get_rewrite_oid(Oid relid, const char *rulename, bool missing_ok)
  * were unique across the entire database.
  */
 Oid
-get_rewrite_oid_without_relid(const char *rulename, Oid *reloid)
+get_rewrite_oid_without_relid(const char *rulename,
+							  Oid *reloid, bool missing_ok)
 {
 	Relation	RewriteRelation;
 	HeapScanDesc scanDesc;
@@ -151,20 +152,26 @@ get_rewrite_oid_without_relid(const char *rulename, Oid *reloid)
 
 	htup = heap_getnext(scanDesc, ForwardScanDirection);
 	if (!HeapTupleIsValid(htup))
-		ereport(ERROR,
-				(errcode(ERRCODE_UNDEFINED_OBJECT),
-				 errmsg("rule \"%s\" does not exist", rulename)));
-
-	ruleoid = HeapTupleGetOid(htup);
-	if (reloid != NULL)
-		*reloid = ((Form_pg_rewrite) GETSTRUCT(htup))->ev_class;
-
-	if (HeapTupleIsValid(htup = heap_getnext(scanDesc, ForwardScanDirection)))
-		ereport(ERROR,
-				(errcode(ERRCODE_DUPLICATE_OBJECT),
-				 errmsg("there are multiple rules named \"%s\"", rulename),
-				 errhint("Specify a relation name as well as a rule name.")));
-
+	{
+		if (!missing_ok)
+			ereport(ERROR,
+					(errcode(ERRCODE_UNDEFINED_OBJECT),
+					 errmsg("rule \"%s\" does not exist", rulename)));
+		ruleoid = InvalidOid;
+	}
+	else
+	{
+		ruleoid = HeapTupleGetOid(htup);
+		if (reloid != NULL)
+			*reloid = ((Form_pg_rewrite) GETSTRUCT(htup))->ev_class;
+
+		htup = heap_getnext(scanDesc, ForwardScanDirection);
+		if (HeapTupleIsValid(htup))
+			ereport(ERROR,
+					(errcode(ERRCODE_DUPLICATE_OBJECT),
+					 errmsg("there are multiple rules named \"%s\"", rulename),
+					 errhint("Specify a relation name as well as a rule name.")));
+	}
 	heap_endscan(scanDesc);
 	heap_close(RewriteRelation, AccessShareLock);
 

src/include/catalog/objectaddress.h

@@ -28,7 +28,8 @@ typedef struct ObjectAddress
 } ObjectAddress;
 
 extern ObjectAddress get_object_address(ObjectType objtype, List *objname,
-				   List *objargs, Relation *relp, LOCKMODE lockmode);
+										List *objargs, Relation *relp,
+										LOCKMODE lockmode, bool missing_ok);
 
 extern void check_object_ownership(Oid roleid,
 					   ObjectType objtype, ObjectAddress address,

src/include/rewrite/rewriteSupport.h

@@ -23,6 +23,7 @@ extern void SetRelationRuleStatus(Oid relationId, bool relHasRules,
 					  bool relIsBecomingView);
 
 extern Oid	get_rewrite_oid(Oid relid, const char *rulename, bool missing_ok);
-extern Oid	get_rewrite_oid_without_relid(const char *rulename, Oid *relid);
+extern Oid	get_rewrite_oid_without_relid(const char *rulename,
+										  Oid *relid, bool missing_ok);
 
 #endif   /* REWRITESUPPORT_H */