doctrine2 - symfony2 I need to connect to 2 different databases. What should I do?

Question

I need to obtain data from two databases in the controller, how to do it?
http://symfony.cn/docs/cookbook/doctrine/multiple_entity_managers.html...
I searched for this answer, but after doing it, it didn't work

Answer 1

Get database A instance

$emA = $this->get('doctrine')->getManager('default');

Get data B instance

$emB = $this->get('doctrine')->getManager('customer');

Get data from the product entity of the A instance

$productsA = $emA->getRepository('AppBundle:Product')->findAll();

Get data from the product entity of the B instance

$productsB = $emB->getRepository('AppBundle:Product')->findAll();