On 2019-Feb-09, Alvaro Herrera wrote:
> I'll put this in the comment.
Attached.
--
Álvaro Herrera https://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index 910e5deaa3f..0d32262c4c3 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -8008,10 +8008,12 @@ CloneFkReferencing(Relation pg_constraint, Relation parentRel,
ReleaseSysCache(partcontup);
/*
- * Looks good! Attach this constraint. Note that the action
- * triggers are no longer needed, so remove them. We identify
- * them because they have our constraint OID, as well as being
- * on the referenced rel.
+ * Looks good! Attach this constraint. The action triggers are
+ * no longer needed -- the parent table already has equivalent
+ * ones, and those will be able to reach the partition, therefore
+ * the ones in the partition are redundant, so remove them. We
+ * identify them because they have our constraint OID, as well as
+ * being on the referenced rel.
*/
trigrel = heap_open(TriggerRelationId, RowExclusiveLock);
ScanKeyInit(&key,
@@ -8024,17 +8026,30 @@ CloneFkReferencing(Relation pg_constraint, Relation parentRel,
while ((trigtup = systable_getnext(scan)) != NULL)
{
Form_pg_trigger trgform = (Form_pg_trigger) GETSTRUCT(trigtup);
+ ObjectAddress trigger;
if (trgform->tgconstrrelid != fk->conrelid)
continue;
if (trgform->tgrelid != fk->confrelid)
continue;
- deleteDependencyRecordsForClass(TriggerRelationId,
- HeapTupleGetOid(trigtup),
- ConstraintRelationId,
- DEPENDENCY_INTERNAL);
- CatalogTupleDelete(trigrel, &trigtup->t_self);
+ /*
+ * The constraint is originally set up to contain this trigger
+ * as an implementation object, so there's a dependency record
+ * that links the two; however, since the trigger is no longer
+ * needed, we remove the dependency link in order to be able
+ * to drop the trigger while keeping the constraint intact.
+ */
+ deleteDependencyRecordsFor(TriggerRelationId,
+ HeapTupleGetOid(trigtup),
+ false);
+ /* make dependency deletion visible to performDeletion */
+ CommandCounterIncrement();
+ ObjectAddressSet(trigger, TriggerRelationId,
+ HeapTupleGetOid(trigtup));
+ performDeletion(&trigger, DROP_RESTRICT, 0);
+ /* make trigger drop visible, in case the loop iterates */
+ CommandCounterIncrement();
}
systable_endscan(scan);
