Query a ManyToMany relation and display the good result in Symfony with Doctrine

Question

in order to know how it really works, there is an unanswered question from Stack website, and notice that I have the similar problem.

In my SQl database, I

Answer 1

You shouldn't use DQL or others direct queries in your controllers if not really necessary. You should do this:

public function indexAdvertsAction() {
    $em=$this->getDoctrine()->getManager();
    $adverts = $em->getRepository('MySpaceMyBundle:Adverts')->findAll();

    return $this->render(
         'MySpaceMyBundle:MyFolder:indexAdverts.html.twig',
         array('adverts' => $adverts )
    );
}

Then, in your template, the advert entity will take care of the rest, thanks to the correct relations mapping:

{% for adverts in advert%}
   <tr>
       <td>{{ adverts.id }}</td>
       <td>{{ adverts.name }}</td>
       <td>{{ adverts.users }}</td>
       <td>
           {% for category in adverts.categories %}
               {{ adverts.categories }}
           {% endfor %}
       </td>
       <td>
           <a href="{{ path('editAdverts', {'name': adverts.name}) }}"><button class="btn btn-warning btn-xs">Edit</button></a>
       </td>
   </tr>
{% endfor %}

Answer 2

WHERE a.categories = c.id

This line should cause the error. I think in your case, you should use a.categories.id instead of a.categories. You can't equalize an object with an integer.