title: doctrine 2 entity is not filled with childs element
body: <p>Within my database I have two related tables.</p>
  
  <p>AppBooking</p>
  
  <p>AppBookingService</p>
  
  <p>AppBookingService has a foreign key to AppBooking</p>
  
  <p>I use this method to make an insertion in both the first and second table.</p>
  
  <pre><code>public function bookingExecute($data){
      try{
          $this-&gt;em-&gt;beginTransaction();
          $appBooking = $this-&gt;_fillAppBooking($data);
          $this-&gt;em-&gt;persist($appBooking);
          if(array_key_exists("appService",$data) &amp;&amp; is_array($data['appService']) &amp;&amp; count($data['appService']) &gt; 0){
              foreach($data['appService'] as  $bookingService){
                  $appBookingService = $this-&gt;_fillAppBookingService($bookingService,$appBooking);
                  $this-&gt;em-&gt;persist($appBookingService);
                  $this-&gt;em-&gt;flush();
              }
          }
          $this-&gt;em-&gt;flush();
          $this-&gt;em-&gt;commit();
          return $appBooking;
      }catch (\Exception $ex){
          $this-&gt;em-&gt;rollback();
          throw new BookingException("",BookingError::BOOKING_QUERY_ERROR);
      }
  }
  </code></pre>
  
  <p>The data is written correctly</p>
  
  <p>After that, in the same http request, I invoke the method below in order to have AppBooking Service data within my entity</p>
  
  <pre><code>$appBooking = $this-&gt;bookingService-&gt;findOne($id);
  </code></pre>
  
  <p>The problem that the AppBooking entity I get does not contain AppBookingService</p>
  
  <p>The method</p>
  
  <pre><code>$appBooking-&gt;getServices()-&gt;count()
  </code></pre>
  
  <p>returns 0</p>
  
  <p>If I make the same call in another http request I get the desired result.</p>
  
  <p>It is as if doctrine did not update the entity in that same request</p>
  
  <p>This is a part of AppBooking</p>
  
  <pre><code>/**
   * @var Collection
   * @ORM\OneToMany(targetEntity="AppBookingService", mappedBy="idBooking")
   */
  private $services;
  
  public function __construct() {
      $this-&gt;services = new ArrayCollection();
  }
  </code></pre>
  
  <p>This is part of AppBookingService</p>
  
  <pre><code>/**
   * @var \Entity\Entity\AppBooking
   *
   * @ORM\ManyToOne(targetEntity="Entity\Entity\AppBooking", inversedBy="services")
   * @ORM\JoinColumns({
   *   @ORM\JoinColumn(name="ID_BOOKING", referencedColumnName="ID_BOOKING", nullable=true)
   * })
   */
  private $idBooking;
  </code></pre>