Rethink behavior of CREATE OR REPLACE during CREATE EXTENSION.

The original implementation simply did nothing when replacing an existing
object during CREATE EXTENSION.  The folly of this was exposed by a report
from Marc Munro: if the existing object belongs to another extension, we
are left in an inconsistent state.  We should insist that the object does
not belong to another extension, and then add it to the current extension
if not already a member.

5 files changed, 16 insertions, 19 deletions

diff --git a/src/backend/commands/foreigncmds.c b/src/backend/commands/foreigncmds.c
index 643ba91bfe1..d16932ba6a0 100644
--- a/src/backend/commands/foreigncmds.c
+++ b/src/backend/commands/foreigncmds.c
@@ -515,7 +515,7 @@ CreateForeignDataWrapper(CreateFdwStmt *stmt)
 	recordDependencyOnOwner(ForeignDataWrapperRelationId, fdwId, ownerId);
 
 	/* dependency on extension */
-	recordDependencyOnCurrentExtension(&myself);
+	recordDependencyOnCurrentExtension(&myself, false);
 
 	/* Post creation hook for new foreign data wrapper */
 	InvokeObjectAccessHook(OAT_POST_CREATE,
@@ -857,7 +857,7 @@ CreateForeignServer(CreateForeignServerStmt *stmt)
 	recordDependencyOnOwner(ForeignServerRelationId, srvId, ownerId);
 
 	/* dependency on extension */
-	recordDependencyOnCurrentExtension(&myself);
+	recordDependencyOnCurrentExtension(&myself, false);
 
 	/* Post creation hook for new foreign server */
 	InvokeObjectAccessHook(OAT_POST_CREATE, ForeignServerRelationId, srvId, 0);
@@ -1137,7 +1137,7 @@ CreateUserMapping(CreateUserMappingStmt *stmt)
 	}
 
 	/* dependency on extension */
-	recordDependencyOnCurrentExtension(&myself);
+	recordDependencyOnCurrentExtension(&myself, false);
 
 	/* Post creation hook for new user mapping */
 	InvokeObjectAccessHook(OAT_POST_CREATE, UserMappingRelationId, umId, 0);
diff --git a/src/backend/commands/functioncmds.c b/src/backend/commands/functioncmds.c
index 03da168ff2c..92abd44a600 100644
--- a/src/backend/commands/functioncmds.c
+++ b/src/backend/commands/functioncmds.c
@@ -1489,6 +1489,7 @@ CreateCast(CreateCastStmt *stmt)
 	char		sourcetyptype;
 	char		targettyptype;
 	Oid			funcid;
+	Oid			castid;
 	int			nargs;
 	char		castcontext;
 	char		castmethod;
@@ -1734,13 +1735,13 @@ CreateCast(CreateCastStmt *stmt)
 
 	tuple = heap_form_tuple(RelationGetDescr(relation), values, nulls);
 
-	simple_heap_insert(relation, tuple);
+	castid = simple_heap_insert(relation, tuple);
 
 	CatalogUpdateIndexes(relation, tuple);
 
 	/* make dependency entries */
 	myself.classId = CastRelationId;
-	myself.objectId = HeapTupleGetOid(tuple);
+	myself.objectId = castid;
 	myself.objectSubId = 0;
 
 	/* dependency on source type */
@@ -1765,11 +1766,10 @@ CreateCast(CreateCastStmt *stmt)
 	}
 
 	/* dependency on extension */
-	recordDependencyOnCurrentExtension(&myself);
+	recordDependencyOnCurrentExtension(&myself, false);
 
 	/* Post creation hook for new cast */
-	InvokeObjectAccessHook(OAT_POST_CREATE,
-						   CastRelationId, myself.objectId, 0);
+	InvokeObjectAccessHook(OAT_POST_CREATE, CastRelationId, castid, 0);
 
 	heap_freetuple(tuple);
 
diff --git a/src/backend/commands/opclasscmds.c b/src/backend/commands/opclasscmds.c
index aff5ac6ec43..2bb0d4c3b5f 100644
--- a/src/backend/commands/opclasscmds.c
+++ b/src/backend/commands/opclasscmds.c
@@ -310,7 +310,7 @@ CreateOpFamily(char *amname, char *opfname, Oid namespaceoid, Oid amoid)
 	recordDependencyOnOwner(OperatorFamilyRelationId, opfamilyoid, GetUserId());
 
 	/* dependency on extension */
-	recordDependencyOnCurrentExtension(&myself);
+	recordDependencyOnCurrentExtension(&myself, false);
 
 	/* Post creation hook for new operator family */
 	InvokeObjectAccessHook(OAT_POST_CREATE,
@@ -713,7 +713,7 @@ DefineOpClass(CreateOpClassStmt *stmt)
 	recordDependencyOnOwner(OperatorClassRelationId, opclassoid, GetUserId());
 
 	/* dependency on extension */
-	recordDependencyOnCurrentExtension(&myself);
+	recordDependencyOnCurrentExtension(&myself, false);
 
 	/* Post creation hook for new operator class */
 	InvokeObjectAccessHook(OAT_POST_CREATE,
diff --git a/src/backend/commands/proclang.c b/src/backend/commands/proclang.c
index b36f31ee6d5..98770c5a61a 100644
--- a/src/backend/commands/proclang.c
+++ b/src/backend/commands/proclang.c
@@ -388,8 +388,7 @@ create_proc_lang(const char *languageName, bool replace,
 	 * Create dependencies for the new language.  If we are updating an
 	 * existing language, first delete any existing pg_depend entries.
 	 * (However, since we are not changing ownership or permissions, the
-	 * shared dependencies do *not* need to change, and we leave them alone.
-	 * We also don't change any pre-existing extension-membership dependency.)
+	 * shared dependencies do *not* need to change, and we leave them alone.)
 	 */
 	myself.classId = LanguageRelationId;
 	myself.objectId = HeapTupleGetOid(tup);
@@ -404,8 +403,7 @@ create_proc_lang(const char *languageName, bool replace,
 								languageOwner);
 
 	/* dependency on extension */
-	if (!is_update)
-		recordDependencyOnCurrentExtension(&myself);
+	recordDependencyOnCurrentExtension(&myself, is_update);
 
 	/* dependency on the PL handler function */
 	referenced.classId = ProcedureRelationId;
diff --git a/src/backend/commands/tsearchcmds.c b/src/backend/commands/tsearchcmds.c
index 3355eaafda2..deac1062ef9 100644
--- a/src/backend/commands/tsearchcmds.c
+++ b/src/backend/commands/tsearchcmds.c
@@ -142,7 +142,7 @@ makeParserDependencies(HeapTuple tuple)
 	recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
 
 	/* dependency on extension */
-	recordDependencyOnCurrentExtension(&myself);
+	recordDependencyOnCurrentExtension(&myself, false);
 
 	/* dependencies on functions */
 	referenced.classId = ProcedureRelationId;
@@ -479,7 +479,7 @@ makeDictionaryDependencies(HeapTuple tuple)
 	recordDependencyOnOwner(myself.classId, myself.objectId, dict->dictowner);
 
 	/* dependency on extension */
-	recordDependencyOnCurrentExtension(&myself);
+	recordDependencyOnCurrentExtension(&myself, false);
 
 	/* dependency on template */
 	referenced.classId = TSTemplateRelationId;
@@ -1069,7 +1069,7 @@ makeTSTemplateDependencies(HeapTuple tuple)
 	recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
 
 	/* dependency on extension */
-	recordDependencyOnCurrentExtension(&myself);
+	recordDependencyOnCurrentExtension(&myself, false);
 
 	/* dependencies on functions */
 	referenced.classId = ProcedureRelationId;
@@ -1417,8 +1417,7 @@ makeConfigurationDependencies(HeapTuple tuple, bool removeOld,
 	recordDependencyOnOwner(myself.classId, myself.objectId, cfg->cfgowner);
 
 	/* dependency on extension */
-	if (!removeOld)
-		recordDependencyOnCurrentExtension(&myself);
+	recordDependencyOnCurrentExtension(&myself, removeOld);
 
 	/* dependency on parser */
 	referenced.classId = TSParserRelationId;