public static function status($queue = "default") {
        $rs = self::runQuery("
            SELECT COUNT(*) as total, COUNT(failed_at) as failed, COUNT(locked_at) as locked
            FROM `" . self::$jobsTable . "`
            WHERE queue = ?
        ", array($queue));
        $rs = $rs[0];

        $failed = $rs["failed"];
        $locked = $rs["locked"];
        $total  = $rs["total"];
        $outstanding = $total - $locked - $failed;

        return array(
            "outstanding" => $outstanding,
            "locked" => $locked,
            "failed" => $failed,
            "total"  => $total
        );
    }