Laravel 5.1LTS specific write connection on select query

<?php
/*
Laravel Connection document
https://laravel.com/docs/5.0/eloquent (compatible with 5.1LTS)
*/

//Eloquent sample
$user = User::onWriteConnection()->find(1);

//Query Builder sample
DB::table('users')->useWritePdo()->get();

//Raw SQL Query sample
DB::selectFromWriteConnection('SELECT * FROM users');