public function leftJoin(
        $foreign_table,
        $master_field = null,
        $join_kind = null,
        $_foreign_alias = null,
        $relation = null
    ) {
        if (!$join_kind) {
            $join_kind = 'left';
        }
        $res = $this->join($foreign_table, $master_field, $join_kind, $_foreign_alias, $relation);
        $res->delete_behaviour = 'ignore';

        return $res;
    }