Symfony-Doctrine : join a table with a view after persisting entity - symfony

Question

In my database, I have a table T and a view V.
The view has some columns of my table and other data (from other tables).
In Symfony, I declared my view as a read-only Entity.
/**
* #ORM\Table(name="V")
* #ORM\Entity(readOnly=true, repositoryClass="AppBundle\Entity\Repository\VRepository")
*/
class V
{
In my T entity, I did a Join :
/**
* #ORM\OneToOne(targetEntity="V")
* #ORM\JoinColumn(name="T_id", referencedColumnName="V_id")
*/
private $view;
And I added just the getter :
/**
* Get view
*
* #return \AppBundle\Entity\V
*/
public function getView()
{
return $this->view;
}
Everything is working well when I want to read and show data.
But I have a problem after persisting a new T entity.
Symfony seems to lost posted data of my form when I create a new T entity (editAction() works perfectly).
An exception occurred while executing 'INSERT INTO T (T_id, T_name, updated_at) VALUES (?, ?, ?)' with params [null, null, "2017-09-01 15:30:41"]:
SQLSTATE[23000]: Integrity constraint violation: 1048 Field 'T_id' cannot be empty (null)
When I remove ORM annotations of the $view property, it creates correctly my new record T in the database.
I think the problem is due to the fact that the V entity (the record in my SQL view) will exist just after the creation of T. And when I persist/flush data in Symfony, V doesn't exist yet. They are "created" at the same time.
I tried to add Doctrine #HasLifecycleCallbacks on my T entity and the #PostPersist event on the getView() method but it doesn't change anything...
Any idea to differ the Join after the creation of the entity ?
I know it's not conventional to use views as entities with Symfony but I haven't other choice.

Answer 1

I've just checked, it works fine with Bidirectional One-To-One relation
In my case tables are defined like:
create table T (`id` int(11) NOT NULL AUTO_INCREMENT, name varchar(100), primary key (id));
create view V as select id as entity, name, '123' as number from T;
Annotations in T:
/**
* #ORM\Table(name="T")
* #ORM\Entity()
*/
class T
{
/**
* #var int
*
* #ORM\Column(name="id", type="integer")
* #ORM\Id
* #ORM\GeneratedValue(strategy="AUTO")
*/
private $id;
/**
* #var string
*
* #ORM\Column(name="name", type="string", length=255, nullable=true)
*/
private $name;
/**
* #var V
*
* #ORM\OneToOne(targetEntity="V", mappedBy="entity")
*/
private $view;
Annotations in V:
/**
* #ORM\Table(name="V")
* #ORM\Entity(readOnly=true)
*/
class V
{
/**
* #var string
*
* #ORM\Column(name="name", type="string", length=255, nullable=true)
*/
private $name;
/**
* #var string
*
* #ORM\Column(name="number", type="string", length=255, nullable=true)
*/
private $number;
/**
* #var T
*
* #ORM\Id
* #ORM\OneToOne(targetEntity="T", inversedBy="view")
* #ORM\JoinColumn(name="entity", referencedColumnName="id")
*/
private $entity;
And a test snippet to prove that it saves, updates and reads fine:
public function testCRUD()
{
/** #var EntityManager $manager */
$manager = $this->client->getContainer()->get('doctrine.orm.default_entity_manager');
$t = new T();
$t->setName('Me');
$manager->persist($t);
$manager->flush();
$t->setName('He');
$manager->flush();
$manager->clear();
/** #var T $t */
$t = $manager->find(T::class, $t->getId());
$this->assertEquals('He', $t->getView()->getName());
}

Answer 2

Based on the #Maksym Moskvychev answer : Prefer a bidirectional One-to-One relation.
T Entity :
/**
* #ORM\OneToOne(targetEntity="V", mappedBy="entity")
*/
private $view;
V Entity :
/**
* #ORM\OneToOne(targetEntity="T", inversedBy="view")
* #ORM\JoinColumn(name="V_id", referencedColumnName="T_id")
*/
private $entity;
Fix the loss of data after posting the addAction() form (new T instance).
In the form where I list all T records :
$builder->add('entity', EntityType::class, array(
'class' => 'AppBundle:T',
'choice_label' => 'id',
'query_builder' => function (EntityRepository $er) {
return $er->createQueryBuilder('t')
->orderBy('t.name', 'ASC')
->setMaxResults(25); // limit the number of results to prevent crash
}
))
Fix the too consuming resources problem (show 25 entities instead of 870+).
Ajax request :
$(".select2").select2({
ajax: {
type : "GET",
url : "{{ path('search_select') }}",
dataType : 'json',
delay : 250,
cache : true,
data : function (params) {
return {
q : params.term, // search term
page : params.page || 1
};
}
}
});
Response for Select2 :
$kwd = $request->query->get('q'); // GET parameters
$page = $request->query->get('page');
$limit = 25;
$offset = ($page - 1) * $limit;
$em = $this->getDoctrine()->getManager();
$repository = $em->getRepository('AppBundle:V');
$qb = $repository->createQueryBuilder('v');
$where = $qb->expr()->orX(
$qb->expr()->like('v.name', ':kwd'),
$qb->expr()->like('v.code', ':kwd')
);
$qb->where($where);
// get the DQL for counting total number of results
$dql = $qb->getDQL();
$results = $qb->orderBy('m.code', 'ASC')
->setFirstResult($offset)
->setMaxResults($limit)
->setParameter('kwd', '%'.$kwd.'%')
->getQuery()->getResult();
// count total number of results
$qc = $em->createQuery($dql)->setParameter('kwd', '%'.$kwd.'%');
$count = count($qc->getResult());
// determine if they are more results or not
$endCount = $offset + $limit;
$morePages = $count > $endCount;
$items = array();
foreach ($results as $r) {
$items[] = array(
'id' => $r->getCode(),
'text' => $r->getName()
);
}
$response = (object) array(
"results" => $items,
"pagination" => array(
"more" => $morePages
)
);
if (!empty($results))
return new Response(json_encode($response));