private function getRandomNumber() {

        $guid = uniqid();

        $updatenumbersql = "UPDATE `{$this->_mysqlprefix}numbers` SET `used` =  '{$guid}' WHERE `used` = '0'  LIMIT 1;";
        $this->_mysqlconn->query($updatenumbersql);

        if($this->_mysqlconn->affected_rows > 0){


            $getnumbersql = "SELECT * FROM `{$this->_mysqlprefix}numbers` WHERE `used` = '{$guid}' LIMIT 1;";
            $getnumberquery = $this->_mysqlconn->query($getnumbersql);
            $number = $getnumberquery->fetch_array();

            return $number['number'];

        }else{

            $numbers = file("http://www.random.org/integers/?num=100&min={$this->_minnumber}&max={$this->_maxnumber}&col=1&base=10&format=plain&rnd=new");

            if(is_array($numbers)){

                $numberstring = "";

                foreach($numbers as $number){
                    $numberstring .= "('{$number}'),";
                }

                $numberstring = rtrim($numberstring, ',');

                $insertnumberssql = "INSERT INTO `{$this->_mysqlprefix}numbers` (`number`) VALUES {$numberstring};";
                $this->_mysqlconn->query($insertnumberssql);

            }

            return $this->getRandomNumber();

        }

    }