Error regarding OneToOne?

Question

symfony

Can't create OneToOne relation in Doctrine
Here is my example:

class User {
...
     /**
     * @ORM\Column(type="string", length=100)
     * @ORM\OneToOne(targetEntity="UserData", mappedBy="user_email")
     */
    private $email;
...
    /**
     * @return string|null
     */
    public function getEmail(): ?string
    {
        return $this->email;
    }

    /**
     * @param string $email
     *
     * @return User
     */
    public function setEmail(string $email): self
    {
        $this->email = $email;

        return $this;
    }
}
class UserData {
...
     /**
     * @ORM\OneToOne(targetEntity="User", inversedBy="email")
     * @ORM\JoinColumn(name="id_user", referencedColumnName="id", onDelete="CASCADE")
     */
    private $user_email;
...
    /**
     * @return mixed
     */
    public function getEmail()
    {
        return $this->user_email;
    }
}

UserDataRepository:

public function findUserById(int $userId)
    {
        $entityManager = $this->getEntityManager();

        $query = $entityManager->createQuery(
            'SELECT ud, u.email as user_email, u.login as user_login
                  FROM App\Entity\UserData ud
                    LEFT JOIN App\Entity\User u WITH ud.id_user = u.id
                  WHERE ud.id_user = :userId'
        )->setParameter('userId', $userId);

        return $query->getOneOrNullResult();
    }

But the result saysNotice: Undefined index: email

Answer 1

Of course it doesn't work. To begin with, it is worth deciding what $email is - a string or a link to UserData.
Then think about what should be in $user_email.
And read the documentation will never be superfluous.
ps If it's quite simple - OneToOne connects two entities through fields, not the fields themselves.