Change many routines to return ObjectAddress rather than OID

The changed routines are mostly those that can be directly called by
ProcessUtilitySlow; the intention is to make the affected object
information more precise, in support for future event trigger changes.
Originally it was envisioned that the OID of the affected object would
be enough, and in most cases that is correct, but upon actually
implementing the event trigger changes it turned out that ObjectAddress
is more widely useful.

Additionally, some command execution routines grew an output argument
that's an object address which provides further info about the executed
command.  To wit:

* for ALTER DOMAIN / ADD CONSTRAINT, it corresponds to the address of
  the new constraint

* for ALTER OBJECT / SET SCHEMA, it corresponds to the address of the
  schema that originally contained the object.

* for ALTER EXTENSION {ADD, DROP} OBJECT, it corresponds to the address
  of the object added to or dropped from the extension.

There's no user-visible change in this commit, and no functional change
either.

Discussion: 20150218213255.GC6717@tamriel.snowman.net
Reviewed-By: Stephen Frost, Andres Freund

1 files changed, 10 insertions, 4 deletions

diff --git a/src/backend/commands/schemacmds.c b/src/backend/commands/schemacmds.c
index a44dbf453e4..722142e16ea 100644
--- a/src/backend/commands/schemacmds.c
+++ b/src/backend/commands/schemacmds.c
@@ -195,13 +195,14 @@ RemoveSchemaById(Oid schemaOid)
 /*
  * Rename schema
  */
-Oid
+ObjectAddress
 RenameSchema(const char *oldname, const char *newname)
 {
 	Oid			nspOid;
 	HeapTuple	tup;
 	Relation	rel;
 	AclResult	aclresult;
+	ObjectAddress address;
 
 	rel = heap_open(NamespaceRelationId, RowExclusiveLock);
 
@@ -243,10 +244,12 @@ RenameSchema(const char *oldname, const char *newname)
 
 	InvokeObjectPostAlterHook(NamespaceRelationId, HeapTupleGetOid(tup), 0);
 
+	ObjectAddressSet(address, NamespaceRelationId, nspOid);
+
 	heap_close(rel, NoLock);
 	heap_freetuple(tup);
 
-	return nspOid;
+	return address;
 }
 
 void
@@ -272,12 +275,13 @@ AlterSchemaOwner_oid(Oid oid, Oid newOwnerId)
 /*
  * Change schema owner
  */
-Oid
+ObjectAddress
 AlterSchemaOwner(const char *name, Oid newOwnerId)
 {
 	Oid			nspOid;
 	HeapTuple	tup;
 	Relation	rel;
+	ObjectAddress address;
 
 	rel = heap_open(NamespaceRelationId, RowExclusiveLock);
 
@@ -291,11 +295,13 @@ AlterSchemaOwner(const char *name, Oid newOwnerId)
 
 	AlterSchemaOwner_internal(tup, rel, newOwnerId);
 
+	ObjectAddressSet(address, NamespaceRelationId, nspOid);
+
 	ReleaseSysCache(tup);
 
 	heap_close(rel, RowExclusiveLock);
 
-	return nspOid;
+	return address;
 }
 
 static void