Class Table Inheritance, repository->findByTypeId - symfony

Question

i'm pretty new to Symfony and Doctrine and i'm facing a problem trying to set Class Table Inheritance. I have a parent Entity, called "TeamActionTarget", and 2 children called "Player" and "Competition".
The model of my parent entity is the following :
// src/Van/TeamsBundle/Entity/TeamActionTarget.php
namespace Van\TeamsBundle\Entity;
use Doctrine\ORM\Mapping as ORM;
/**
* Van\TeamsBundle\Entity\TeamActionTarget
*
* #ORM\Entity
* #ORM\Table(name="van_teams_actions_targets")
* #ORM\InheritanceType("JOINED")
* #ORM\DiscriminatorColumn(name="type_id", type="integer")
* #ORM\DiscriminatorMap( {"1" = "Competition", "2" = "Player"} )
*/
abstract class TeamActionTarget
{
/**
* #var integer $id
*
* #ORM\Column(name="id", type="integer")
* #ORM\Id
* #ORM\GeneratedValue(strategy="AUTO")
*/
private $id;
/**
* Get id
*
* #return integer
*/
public function getId()
{
return $this->id;
}
}
Doctrine2 generated me a parent table, with 2 fields, "id" and "type_id", and 2 children tables, with their own unique fields.
What I want to do now is to retrieve all children BY TYPE, from an integer value posted from a form.
So in a controller, I coded this :
$em->getRepository('VanTeamsBundle:TeamActionTarget')->findByTypeId($targetType);
But Symfony2 returns me an error :
Entity "Van\TeamsBundle\Entity\TeamActionTarget" has no field "typeId"
Which is true. The entity model doesn't contain this field, only the parent class does. So I tried to add this field in the entity model, but I get a error when trying to update the entity, saying there is a conflict between this field and the discriminator.
My question is pretty easy, How can I retrieve my children BY TYPE, posted from a form ?

Answer 1

When using single table inheritance, you have to use the repository of the child class directly:
$em->getRepository('VanTeamsBundle:Player')->findAll();
If you would like to retrieve the different child entities dependent on a form, you have to use the entity alias (e.g. VanTeamsBundle:Player) as the form field value and pass it to the getRepository() method. Another way of doing this is by performing a custom mapping between the form field value and the entity alias using data transformers.