title: doctrine2 - how to use DATE_ADD function
body: <p>I am trying to use the <code>DATE_ADD</code> function from doctrine2 but I am having trouble get it right.</p>
  
  <p>I am using like this in DQL:</p>
  
  <pre><code>-&gt;andWhere('p.created_at &lt;= DATE_ADD(CURRENT_DATE(),4, day)')
  </code></pre>
  
  <p>but I am getting syntax error:</p>
  
  <blockquote>
    <p>[Syntax Error] line 0, col 215: Error: Expected'.' or '(', got 'day'</p>
  </blockquote>
  
  <p>I tried different implementations but I allways get some kind of syntax errror.</p>
  
  <p>I have checked DoctrineExtensions which contain this function, but I shouldnt need it because the function is already included in doctrine.</p>