diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index d678519284..1974c13798 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -9397,7 +9397,7 @@ ATExecAlterConstraint(Relation rel, AlterTableCmd *cmd,
 			copy_tg->tginitdeferred = cmdcon->initdeferred;
 			CatalogTupleUpdate(tgrel, &copyTuple->t_self, copyTuple);
 
-			InvokeObjectPostAlterHook(TriggerRelationId, currcon->oid, 0);
+			InvokeObjectPostAlterHook(TriggerRelationId, tgform->oid, 0);
 
 			heap_freetuple(copyTuple);
 		}