public static function getInstance($database, $anonymous = false)
    {
        if ($anonymous || !array_key_exists($database, self::$instances)) {
            $instance = new Medoo(self::getDatabaseConfig($database));
            if ($anonymous) {
                return $instance;
            }
            self::$instances[$database] = $instance;
        }

        return self::$instances[$database];
    }