title: Doctrine2 - Joining Entities without Associations Using ORM QueryBuilder
body: <p>Is it possible to generate the query for Joining unassociated Entities using the ORM QueryBuilder as in :  </p>
  
  <pre><code>$query = $em-&gt;createQuery('SELECT u FROM User u JOIN Blacklist b WITH u.email = b.email');
  </code></pre>