Model\Message::deleteOuttimeMessage PHP Method

    public static function deleteOuttimeMessage()
    {
        $inTransaction = DB::getInstance()->inTransaction();
        if (!$inTransaction) {
            DB::getInstance()->beginTransaction();
        }
        $statement = DB::getInstance()->prepare("DELETE FROM `message` WHERE pushEndTime< :pushEndTime");
        $statement->bindValue(':pushEndTime', time(), DB::PARAM_INT);
        $result = $statement->execute();
        if (!$inTransaction) {
            DB::getInstance()->commit();
        }
        return $result;
    }