Performing a custom query inside Doctrine entity - php

Question

I have an entity (B) which is responsible for managing custom templates. Upon updating entity A I need to query entity B to fetch the desired template and do the necessary processing.
Something like:
use Doctrine\ORM\Mapping as ORM;
use Doctrine\ORM\EntityRepository;
use Bundle\EmailsBundle\Entity\Email;
use Symfony\Component\Validator\ExecutionContextInterface;
class MemberApplication extends EntityRepository
{
public function sendUpdateNotificationEmails()
{
// Send email to user
$emailRow = $this->getEntityManager()
->createQuery("SELECT * FROM emails where `type` = 'x' LIMIT 1")
->getResult();
}
(...)
}
This returns me an error:
Fatal error: Call to a member function createQuery() on a non-object in Classpath/Classname.php
Both $this->getEntityManager() and $this->_em is NULL.
I read a similar approach in http://symfony.com/doc/current/book/doctrine.html#custom-repository-classes and I'm unable to figure out why this isn't working.
Thanks

Answer 1

this->getEntityManager() returns null because the dependence on doctrine is not injected. Try $this->getDoctrine()->getEntityManager(); instead. This should be done in the controller side though so something like this:
$em = $this->getDoctrine()->getManager();
$memberRepo = $em->getRepository('MyBundle:MemberApplication');
$result = $memberRepo->sendUpdateNotificationEmails();
then in your function you should return $emailRow or what you want.