src/Config/Config.php
protected static function checkDatabase($key)
    {
        $driver = self::$params['database']['default'];
        //
        if (array_key_exists($key, self::$params['database'])) {
            return true;
        } elseif (array_key_exists($key, self::$params['database']['connections'][$driver])) {
            return true;
        } else {
            self::exception('database', $key);
        }
    }
protected static function checkDatabase($key)
    {
        $driver = self::$params['database']['default'];
        //
        if (array_key_exists($key, self::$params['database'])) {
            return true;
        } elseif (array_key_exists($key, self::$params['database']['connections'][$driver])) {
            return true;
        } else {
            self::exception('database', $key);
        }
    }
protected static function checkDatabase ( $ key ) { $ driver = self :: $ params [ 'database' ] [ 'default' ] ; // if ( array_key_exists ( $ key , self :: $ params [ 'database' ] ) ) { return true ; } elseif ( array_key_exists ( $ key , self :: $ params [ 'database' ] [ 'connections' ] [ $ driver ] ) ) { return true ; } else { self :: exception ( 'database' , $ key ) ; } }
check if secondary parameter exists if primary parameter is 'database'.

@param $key(string) primary and secondary parameter concatenated
check if secondary parameter exists if primary parameter is database .