At the moment I am learning how to use Symfony2. I got to the point where they explain how to use Doctrine.
In the examples given they sometimes use the entity manager:
$em = $this->getDoctrine()->getEntityManager();
$products = $em->getRepository('AcmeStoreBundle:Product')
->findAllOrderedByName();
and in other examples the entity manager is not used:
$product = $this->getDoctrine()
->getRepository('AcmeStoreBundle:Product')
->find($id);
So I actually tried the first example without getting the entity manager:
$repository = $this->getDoctrine()
->getRepository('AcmeStoreBundle:Product');
$products = $repository->findAllOrderedByName();
and got the same results.
So when do i actually need the entity manager and when is it OK to just go for the repository at once?
Looking at Controller
getDoctrine()
equals to $this->get('doctrine')
, an instance of Symfony\Bundle\DoctrineBundle\Registry
. Registry provides:
getEntityManager()
returning Doctrine\ORM\EntityManager
, which in turn provides getRepository()
getRepository()
returning Doctrine\ORM\EntityRepository
Thus, $this->getDoctrine()->getRepository()
equals $this->getDoctrine()->getEntityManager()->getRepository()
.
Entity manager is useful when you want to persist or remove an entity:
$em = $this->getDoctrine()->getEntityManager();
$em->persist($myEntity);
$em->flush();
If you are just fetching data, you can get only the repository:
$repository = $this->getDoctrine()->getRepository('AcmeStoreBundle:Product');
$product = $repository->find(1);
Or better, if you are using custom repositories, wrap getRepository()
in a controller function as you can get auto-completition feature from your IDE:
/**
* @return \Acme\HelloBundle\Repository\ProductRepository
*/
protected function getProductRepository()
{
return $this->getDoctrine()->getRepository('AcmeHelloBundle:Product');
}