title: Symfony 4 - Forms CollectionType get specific data
body: <p>I have two kind of entities : "Affaire" and "Pointage". My Affaire Entity has a OneToMany relation with my Pointage Entity :</p>
  
  <pre><code>//App\Entity\Affaire.php
  
  /**
   * @ORM\OneToMany(targetEntity="App\Entity\Pointage", mappedBy="numAffaire")
   */
      private $pointages;
  </code></pre>
  
  <pre><code>//App\Entity\Pointage.php
  
  /**
   * @ORM\ManyToOne(targetEntity="App\Entity\Affaires", inversedBy="pointages")
   * @ORM\JoinColumn(nullable=false)
   */
      private $numAffaire;
  </code></pre>
  
  <p>I created a form for my Affaire Entity which get "Pointages" related to a "Affaire". </p>
  
  <pre><code>//App\Form\AffaireType.php
  
  class AffaireType extends AbstractType
  {
      public function buildForm(FormBuilderInterface $builder, array $options)
      {
          $builder-&gt;add('numAffaire');
          $builder-&gt;add('descAffaire');
          $builder-&gt;add('pointages', CollectionType::class, [
              'entry_type' =&gt; PointageType::class,
              'entry_options' =&gt; ['label' =&gt; false, 'pointages' =&gt; $options['pointages']],
          ]);
      }
  
      public function configureOptions(OptionsResolver $resolver)
      {
          $resolver-&gt;setRequired(['pointages']);
          $resolver-&gt;setDefaults([
              'data_class' =&gt; Affaires::class,
          ]);
      }
  
  }
  
  </code></pre>
  
  <pre><code>//App\Form\PointageType.php
  
  class PointageType extends AbstractType
  {
      public function buildForm(FormBuilderInterface $builder, array $options)
      {
          $builder-&gt;add('heurePointage');
      }
  
      public function configureOptions(OptionsResolver $resolver)
      {
          $resolver-&gt;setRequired(['pointages']);
          $resolver-&gt;setDefaults([
              'data_class' =&gt; Pointage::class,
          ]);
      }
  }
  </code></pre>
  
  <p>My question is : how can I filter the "Pointages" in my AffaireType class ? For example, I want to get all the pointages associated to my Affaire where the id of my pointages is less than 100. Is it possible to make a query somewhere ?</p>