protected function getQueueId($name)
    {
        $r = $this->db->fetchColumn('select queue_id from Queues where queue_name = ? limit 1', [$name]);

        if ($r === false) {
            throw new RuntimeException(t('Queue does not exist: %s', $name));
        }

        $count = (int) $r;

        return $count;
    }