title: Get related and unrelated rows at the same queryBuilder
body: <p>I have two entities that until recently had no related but now, for statistical reasons I had to relate.</p>
  
  <p>The fact is that now I have X number of unrelated records that my client has asked me to show in statistics as "unknown origin".</p>
  
  <p>I must create a list of "products" with its origin and making products that are not related, show as origin "unknown origin".</p>
  
  <p>This can be done through a QueryBuilder?</p>
  
  <p>I paste a sample of my queryBuilder.</p>
  
  <pre><code>    $query = $this-&gt;createQueryBuilder('p')
                  -&gt;select('p')
                  -&gt;where('p.provider = :provider')
                  -&gt;join('p.inventory', 'i')
                  -&gt;setParameter('provider', $provider);
  </code></pre>
  
  <p>It returns me just related results.</p>
  
  <p>Some tips?</p>
  
  <p>Thanks.</p>