Тут не нужна другая сущность.
One-To-Many, Self-referencing
You can also setup a one-to-many association that is self-referencing. In this example we setup a hierarchy of Category objects by creating a self referencing relationship. This effectively models a hierarchy of categories and from the database perspective is known as an adjacency list approach.
class User
{
/**
* Кого пригласил
* @var ArrayCollection
* @ORM\OneToMany(targetEntity="User", mappedBy="invitedBy")
*/
private $invitedMembers;
/**
* Кем был приглашен
* @var User
* @ORM\ManyToOne(targetEntity="User", inversedBy="invitedMembers")
*/
private $invitedBy;
public function __construct() {
$this->invitedMembers = new \Doctrine\Common\Collections\ArrayCollection();
}
}
