Using multiple databases with Symfony2 and Doctrine2

I was looking for documentation on how to use multiple databases with Symfony and all the results were talking about having 2 connections with 2 entity managers and adding mappings for each bundle ...too complicated for a simple thing.

But I kept on searching and I found this article:  https://techpunch.co.uk/development/using-multiple-databases-with-symfony2-and-doctrine2  which is saying:

"
You will need to use only connection that spans all of your databases, if you want to build a relationship between entities then they must use the same connection. Do to this you will need a user that has access to all of the databases the you wish to access. Setup this user as per usual within your Symfony2 application, for the database name just select one of the databases, it doesn't matter which one.
No extra Doctrine config is needed to get this working, ....

The key to getting multiple databases to work is within your entity classes, you need to specify the table name of the entity with a prefix of the name of the database to which the table belongs. Here is an example using annotations:

<?php
namespace Demo\UserBundle\Entity;

use DoctrineORMMapping as ORM;

/**
 * Demo\UserBundle\Entity\User
 *
 * @ORMTable(name="users.User")
 */
class User implements
{
  /* ... */

"
I tried this solution on my project and worked fine.

You may want to look also at Doctrine's  Master-Slave Connection:  http://blog.alejandrocelaya.com/2014/04/18/configure-multiple-database-connections-in-doctrine-with-zend-framework-2-2/