title: Select One column Doctrine DQL
body: <p>I need a simple column for a table.</p>
  
  <p>By example a table "project", with column <code>id</code>, <code>name</code> and <code>year</code>.</p>
  
  <p>If I do:</p>
  
  <pre><code>$q = Doctrine_Query::create()
          -&gt;select('a.pro_id')
          -&gt;from('fndr_proyecto a')
          -&gt;where('a.pro_id =?',1);
      $pro = $q-&gt;execute();
      json_encode($pro-&gt;toArray());
  </code></pre>
  
  <p>The answer is all column like</p>
  
  <pre><code>{"id":1,"name":"Project name","year":2013}
  </code></pre>
  
  <p>but I need only one column. I expect:</p>
  
  <pre><code>{"id":1}
  </code></pre>
  
  <p>It is with DQL because with native SQL work fine.</p>
  
  <p>The ORM is build automaticaly with a Visual Paradigm.</p>