Support ALTER TYPE RENAME. Petr Jelinek

Author: tglsfdc

doc/src/sgml/ref/alter_type.sgml

@@ -1,5 +1,5 @@
 <!--
-$PostgreSQL: pgsql/doc/src/sgml/ref/alter_type.sgml,v 1.4 2006/09/16 00:30:16 momjian Exp $
+$PostgreSQL: pgsql/doc/src/sgml/ref/alter_type.sgml,v 1.5 2008/03/19 18:38:29 tgl Exp $
 PostgreSQL documentation
 -->
 
@@ -24,6 +24,7 @@ PostgreSQL documentation
 
  <refsynopsisdiv>
   <synopsis>
+ALTER TYPE <replaceable class="PARAMETER">name</replaceable> RENAME TO <replaceable class="PARAMETER">new_name</replaceable>
 ALTER TYPE <replaceable class="PARAMETER">name</replaceable> OWNER TO <replaceable class="PARAMETER">new_owner</replaceable> 
 ALTER TYPE <replaceable class="PARAMETER">name</replaceable> SET SCHEMA <replaceable class="PARAMETER">new_schema</replaceable>
   </synopsis>
@@ -34,8 +35,6 @@ ALTER TYPE <replaceable class="PARAMETER">name</replaceable> SET SCHEMA <replace
 
   <para>
    <command>ALTER TYPE</command> changes the definition of an existing type.
-   The only currently available capabilities are changing the owner and schema
-   of a type.
   </para>
 
   <para>
@@ -65,6 +64,15 @@ ALTER TYPE <replaceable class="PARAMETER">name</replaceable> SET SCHEMA <replace
       </listitem>
      </varlistentry>
 
+     <varlistentry>
+      <term><replaceable class="PARAMETER">new_name</replaceable></term>
+      <listitem>
+       <para>
+        The new name for the type.
+       </para>
+      </listitem>
+     </varlistentry>
+
      <varlistentry>
       <term><replaceable class="PARAMETER">new_owner</replaceable></term>
       <listitem>
@@ -91,15 +99,22 @@ ALTER TYPE <replaceable class="PARAMETER">name</replaceable> SET SCHEMA <replace
   <title>Examples</title>
 
   <para> 
-   To change the owner of the user-defined type <literal>email</literal>
+   To rename a data type:
+   <programlisting>
+ALTER TYPE electronic_mail RENAME TO email;
+   </programlisting>
+  </para>
+
+  <para> 
+   To change the owner of the type <literal>email</literal>
    to <literal>joe</literal>:
    <programlisting>
 ALTER TYPE email OWNER TO joe;
    </programlisting>
   </para>
 
   <para>
-   To change the schema of the user-defined type <literal>email</literal>
+   To change the schema of the type <literal>email</literal>
    to <literal>customers</literal>:
    <programlisting>
 ALTER TYPE email SET SCHEMA customers;

src/backend/catalog/pg_type.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/catalog/pg_type.c,v 1.115 2008/01/01 19:45:48 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/catalog/pg_type.c,v 1.116 2008/03/19 18:38:30 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -552,15 +552,16 @@ GenerateTypeDependencies(Oid typeNamespace,
 }
 
 /*
- * TypeRename
+ * RenameTypeInternal
  *		This renames a type, as well as any associated array type.
  *
- * Note: this isn't intended to be a user-exposed function; it doesn't check
- * permissions etc.  (Perhaps TypeRenameInternal would be a better name.)
- * Currently this is only used for renaming table rowtypes.
+ * Caller must have already checked privileges.
+ *
+ * Currently this is used for renaming table rowtypes and for
+ * ALTER TYPE RENAME TO command.
  */
 void
-TypeRename(Oid typeOid, const char *newTypeName, Oid typeNamespace)
+RenameTypeInternal(Oid typeOid, const char *newTypeName, Oid typeNamespace)
 {
 	Relation	pg_type_desc;
 	HeapTuple	tuple;
@@ -606,7 +607,7 @@ TypeRename(Oid typeOid, const char *newTypeName, Oid typeNamespace)
 	{
 		char	   *arrname = makeArrayTypeName(newTypeName, typeNamespace);
 
-		TypeRename(arrayOid, arrname, typeNamespace);
+		RenameTypeInternal(arrayOid, arrname, typeNamespace);
 		pfree(arrname);
 	}
 }
@@ -706,7 +707,7 @@ moveArrayTypeName(Oid typeOid, const char *typeName, Oid typeNamespace)
 	newname = makeArrayTypeName(typeName, typeNamespace);
 
 	/* Apply the rename */
-	TypeRename(typeOid, newname, typeNamespace);
+	RenameTypeInternal(typeOid, newname, typeNamespace);
 
 	/*
 	 * We must bump the command counter so that any subsequent use of

src/backend/commands/alter.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/commands/alter.c,v 1.27 2008/02/07 21:07:55 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/alter.c,v 1.28 2008/03/19 18:38:30 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -117,7 +117,7 @@ ExecRenameStmt(RenameStmt *stmt)
 								aclcheck_error(aclresult, ACL_KIND_NAMESPACE,
 											get_namespace_name(namespaceId));
 
-							renamerel(relid, stmt->newname, stmt->renameType);
+							RenameRelation(relid, stmt->newname, stmt->renameType);
 							break;
 						}
 					case OBJECT_COLUMN:
@@ -154,6 +154,10 @@ ExecRenameStmt(RenameStmt *stmt)
 			RenameTSConfiguration(stmt->object, stmt->newname);
 			break;
 
+		case OBJECT_TYPE:
+			RenameType(stmt->object, stmt->newname);
+			break;
+
 		default:
 			elog(ERROR, "unrecognized rename stmt type: %d",
 				 (int) stmt->renameType);

src/backend/commands/tablecmds.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/commands/tablecmds.c,v 1.242 2008/02/07 17:09:51 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/tablecmds.c,v 1.243 2008/03/19 18:38:30 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1612,47 +1612,32 @@ renameatt(Oid myrelid,
 	relation_close(targetrelation, NoLock);		/* close rel but keep lock */
 }
 
+
 /*
- *		renamerel		- change the name of a relation
+ * Execute ALTER TABLE/INDEX/SEQUENCE/VIEW RENAME
  *
- *		XXX - When renaming sequences, we don't bother to modify the
- *			  sequence name that is stored within the sequence itself
- *			  (this would cause problems with MVCC). In the future,
- *			  the sequence name should probably be removed from the
- *			  sequence, AFAIK there's no need for it to be there.
+ * Caller has already done permissions checks.
  */
 void
-renamerel(Oid myrelid, const char *newrelname, ObjectType reltype)
+RenameRelation(Oid myrelid, const char *newrelname, ObjectType reltype)
 {
 	Relation	targetrelation;
-	Relation	relrelation;	/* for RELATION relation */
-	HeapTuple	reltup;
-	Form_pg_class relform;
 	Oid			namespaceId;
-	char	   *oldrelname;
 	char		relkind;
-	bool		relhastriggers;
 
 	/*
 	 * Grab an exclusive lock on the target table, index, sequence or view,
 	 * which we will NOT release until end of transaction.
 	 */
 	targetrelation = relation_open(myrelid, AccessExclusiveLock);
 
-	oldrelname = pstrdup(RelationGetRelationName(targetrelation));
 	namespaceId = RelationGetNamespace(targetrelation);
-
-	if (!allowSystemTableMods && IsSystemRelation(targetrelation))
-		ereport(ERROR,
-				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
-				 errmsg("permission denied: \"%s\" is a system catalog",
-						RelationGetRelationName(targetrelation))));
+	relkind = targetrelation->rd_rel->relkind;
 
 	/*
 	 * For compatibility with prior releases, we don't complain if ALTER TABLE
 	 * or ALTER INDEX is used to rename a sequence or view.
 	 */
-	relkind = targetrelation->rd_rel->relkind;
 	if (reltype == OBJECT_SEQUENCE && relkind != RELKIND_SEQUENCE)
 		ereport(ERROR,
 				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
@@ -1665,7 +1650,48 @@ renamerel(Oid myrelid, const char *newrelname, ObjectType reltype)
 				 errmsg("\"%s\" is not a view",
 						RelationGetRelationName(targetrelation))));
 
-	relhastriggers = (targetrelation->rd_rel->reltriggers > 0);
+	/*
+	 * Don't allow ALTER TABLE on composite types.
+	 * We want people to use ALTER TYPE for that.
+	 */
+	if (relkind == RELKIND_COMPOSITE_TYPE)
+		ereport(ERROR,
+				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
+				 errmsg("\"%s\" is a composite type",
+						RelationGetRelationName(targetrelation)),
+				 errhint("Use ALTER TYPE instead.")));
+
+	/* Do the work */
+	RenameRelationInternal(myrelid, newrelname, namespaceId);
+
+	/*
+	 * Close rel, but keep exclusive lock!
+	 */
+	relation_close(targetrelation, NoLock);
+}
+
+/*
+ *		RenameRelationInternal - change the name of a relation
+ *
+ *		XXX - When renaming sequences, we don't bother to modify the
+ *			  sequence name that is stored within the sequence itself
+ *			  (this would cause problems with MVCC). In the future,
+ *			  the sequence name should probably be removed from the
+ *			  sequence, AFAIK there's no need for it to be there.
+ */
+void
+RenameRelationInternal(Oid myrelid, const char *newrelname, Oid namespaceId)
+{
+	Relation	targetrelation;
+	Relation	relrelation;	/* for RELATION relation */
+	HeapTuple	reltup;
+	Form_pg_class relform;
+
+	/*
+	 * Grab an exclusive lock on the target table, index, sequence or
+	 * view, which we will NOT release until end of transaction.
+	 */
+	targetrelation = relation_open(myrelid, AccessExclusiveLock);
 
 	/*
 	 * Find relation's pg_class tuple, and make sure newrelname isn't in use.
@@ -1703,12 +1729,13 @@ renamerel(Oid myrelid, const char *newrelname, ObjectType reltype)
 	 * Also rename the associated type, if any.
 	 */
 	if (OidIsValid(targetrelation->rd_rel->reltype))
-		TypeRename(targetrelation->rd_rel->reltype, newrelname, namespaceId);
+		RenameTypeInternal(targetrelation->rd_rel->reltype,
+						   newrelname, namespaceId);
 
 	/*
 	 * Also rename the associated constraint, if any.
 	 */
-	if (relkind == RELKIND_INDEX)
+	if (targetrelation->rd_rel->relkind == RELKIND_INDEX)
 	{
 		Oid			constraintId = get_index_constraint(myrelid);
 

src/backend/commands/typecmds.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/commands/typecmds.c,v 1.113 2008/01/01 19:45:49 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/typecmds.c,v 1.114 2008/03/19 18:38:30 tgl Exp $
  *
  * DESCRIPTION
  *	  The "DefineFoo" routines take the parse tree and pick out the
@@ -2339,6 +2339,76 @@ GetDomainConstraints(Oid typeOid)
 	return result;
 }
 
+
+/*
+ * Execute ALTER TYPE RENAME
+ */
+void
+RenameType(List *names, const char *newTypeName)
+{
+	TypeName   *typename;
+	Oid			typeOid;
+	Relation	rel;
+	HeapTuple	tup;
+	Form_pg_type typTup;
+
+	/* Make a TypeName so we can use standard type lookup machinery */
+	typename = makeTypeNameFromNameList(names);
+	typeOid = typenameTypeId(NULL, typename, NULL);
+
+	/* Look up the type in the type table */
+	rel = heap_open(TypeRelationId, RowExclusiveLock);
+
+	tup = SearchSysCacheCopy(TYPEOID,
+							 ObjectIdGetDatum(typeOid),
+							 0, 0, 0);
+	if (!HeapTupleIsValid(tup))
+		elog(ERROR, "cache lookup failed for type %u", typeOid);
+	typTup = (Form_pg_type) GETSTRUCT(tup);
+
+	/* check permissions on type */
+	if (!pg_type_ownercheck(typeOid, GetUserId()))
+		aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_TYPE,
+					   format_type_be(typeOid));
+
+	/*
+	 * If it's a composite type, we need to check that it really is a
+	 * free-standing composite type, and not a table's rowtype. We
+	 * want people to use ALTER TABLE not ALTER TYPE for that case.
+	 */
+	if (typTup->typtype == TYPTYPE_COMPOSITE &&
+		get_rel_relkind(typTup->typrelid) != RELKIND_COMPOSITE_TYPE)
+		ereport(ERROR,
+				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
+				 errmsg("%s is a table's row type",
+						format_type_be(typeOid)),
+				 errhint("Use ALTER TABLE instead.")));
+
+	/* don't allow direct alteration of array types, either */
+	if (OidIsValid(typTup->typelem) &&
+		get_array_type(typTup->typelem) == typeOid)
+		ereport(ERROR,
+				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
+				 errmsg("cannot alter array type %s",
+						format_type_be(typeOid)),
+				 errhint("You can alter type %s, which will alter the array type as well.",
+						 format_type_be(typTup->typelem))));
+
+	/* 
+	 * If type is composite we need to rename associated pg_class entry too.
+	 * RenameRelationInternal will call RenameTypeInternal automatically.
+	 */
+	if (typTup->typtype == TYPTYPE_COMPOSITE)
+		RenameRelationInternal(typTup->typrelid, newTypeName,
+							   typTup->typnamespace);
+	else
+		RenameTypeInternal(typeOid, newTypeName,
+						   typTup->typnamespace);
+
+	/* Clean up */
+	heap_close(rel, RowExclusiveLock);
+}
+
 /*
  * Change the owner of a type.
  */

src/backend/parser/gram.y

@@ -11,7 +11,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/parser/gram.y,v 2.607 2008/02/15 22:17:06 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/parser/gram.y,v 2.608 2008/03/19 18:38:30 tgl Exp $
  *
  * HISTORY
  *	  AUTHOR			DATE			MAJOR EVENT
@@ -4734,6 +4734,14 @@ RenameStmt: ALTER AGGREGATE func_name aggr_args RENAME TO name
 					n->newname = $8;
 					$$ = (Node *)n;
 				}
+			| ALTER TYPE_P any_name RENAME TO name
+				{
+					RenameStmt *n = makeNode(RenameStmt);
+					n->renameType = OBJECT_TYPE;
+					n->object = $3;
+					n->newname = $6;
+					$$ = (Node *)n;
+				}
 		;
 
 opt_column: COLUMN									{ $$ = COLUMN; }

src/backend/tcop/utility.c

@@ -10,7 +10,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/tcop/utility.c,v 1.290 2008/03/14 17:25:58 alvherre Exp $
+ *	  $PostgreSQL: pgsql/src/backend/tcop/utility.c,v 1.291 2008/03/19 18:38:30 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1613,6 +1613,9 @@ CreateCommandTag(Node *parsetree)
 				case OBJECT_TSCONFIGURATION:
 					tag = "ALTER TEXT SEARCH CONFIGURATION";
 					break;
+				case OBJECT_TYPE:
+					tag = "ALTER TYPE";
+					break;
 				default:
 					tag = "???";
 					break;