Database [] not configured Laravel 5

I create new db in phpmyadmin and new tables.

Then i do

    public function next(Request $request){
    $langs = DB::connection('mydb')->select('select * from lang');
    }

and get

Database [compgen] not configured.

in my .env

DB_HOST=localhost
DB_DATABASE=test
DB_USERNAME=root
DB_PASSWORD=123

in my config/database.php

        'mysql' => [
        'driver'    => 'mysql',
        'host'      => env('DB_HOST', 'localhost'),
        'database'  => env('DB_DATABASE', 'test'),
        'username'  => env('DB_USERNAME', 'root'),
        'password'  => env('DB_PASSWORD', '123'),
        'charset'   => 'utf8',
        'collation' => 'utf8_unicode_ci',
        'prefix'    => 'test_',
        'strict'    => false,
    ],

via Chebli Mohamed