getOwnedSequences(Oid relid, AttrNumber attnum)
{
	List	   *result = NIL;
	Relation	depRel;
	ScanKeyData key[3];
	SysScanDesc scan;
	HeapTuple	tup;

	depRel = table_open(DependRelationId, AccessShareLock);

	ScanKeyInit(&key[0],
				Anum_pg_depend_refclassid,
				BTEqualStrategyNumber, F_OIDEQ,
				ObjectIdGetDatum(RelationRelationId));
	ScanKeyInit(&key[1],
				Anum_pg_depend_refobjid,
				BTEqualStrategyNumber, F_OIDEQ,
				ObjectIdGetDatum(relid));
	if (attnum)
		ScanKeyInit(&key[2],
					Anum_pg_depend_refobjsubid,
					BTEqualStrategyNumber, F_INT4EQ,
					Int32GetDatum(attnum));

	scan = systable_beginscan(depRel, DependReferenceIndexId, true,
							  NULL, attnum ? 3 : 2, key);

	while (HeapTupleIsValid(tup = systable_getnext(scan)))
	{
		Form_pg_depend deprec = (Form_pg_depend) GETSTRUCT(tup);

		/*
		 * We assume any auto or internal dependency of a sequence on a column
		 * must be what we are looking for.  (We need the relkind test because
		 * indexes can also have auto dependencies on columns.)
		 */
		if (deprec->classid == RelationRelationId &&
			deprec->objsubid == 0 &&
			deprec->refobjsubid != 0 &&
			(deprec->deptype == DEPENDENCY_AUTO || deprec->deptype == DEPENDENCY_INTERNAL) &&
			get_rel_relkind(deprec->objid) == RELKIND_SEQUENCE)
		{
			result = lappend_oid(result, deprec->objid);
		}
	}

	systable_endscan(scan);

	table_close(depRel, AccessShareLock);

	return result;
}
getOwnedSequences(Oid relid, AttrNumber attnum)
{
	List	   *result = NIL;
	Relation	depRel;
	ScanKeyData key[3];
	SysScanDesc scan;
	HeapTuple	tup;

	depRel = table_open(DependRelationId, AccessShareLock);

	ScanKeyInit(&key[0],
				Anum_pg_depend_refclassid,
				BTEqualStrategyNumber, F_OIDEQ,
				ObjectIdGetDatum(RelationRelationId));
	ScanKeyInit(&key[1],
				Anum_pg_depend_refobjid,
				BTEqualStrategyNumber, F_OIDEQ,
				ObjectIdGetDatum(relid));
	if (attnum)
		ScanKeyInit(&key[2],
					Anum_pg_depend_refobjsubid,
					BTEqualStrategyNumber, F_INT4EQ,
					Int32GetDatum(attnum));

	scan = systable_beginscan(depRel, DependReferenceIndexId, true,
							  NULL, attnum ? 3 : 2, key);

	while (HeapTupleIsValid(tup = systable_getnext(scan)))
	{
		Form_pg_depend deprec = (Form_pg_depend) GETSTRUCT(tup);

		 
		if (deprec->classid == RelationRelationId &&
			deprec->objsubid == 0 &&
			deprec->refobjsubid != 0 &&
			(deprec->deptype == DEPENDENCY_AUTO || deprec->deptype == DEPENDENCY_INTERNAL) &&
			get_rel_relkind(deprec->objid) == RELKIND_SEQUENCE)
		{
			result = lappend_oid(result, deprec->objid);
		}
	}

	systable_endscan(scan);

	table_close(depRel, AccessShareLock);

	return result;
}