title: Swift and Parse.com : relational query
body: <p>On parse.com, I have a table named "ExerciseInstance" with a "pointer" to the "_User" table (with the user's objectId).</p>
  
  <p>In my Swift code, I want to get all the rows from ExerciseInstance with UserAccount&lt;_User>  = "MZmMHtobwQ"</p>
  
  <p>This does not work:</p>
  
  <pre><code>predicate = NSPredicate(format:"userAccount == %@", "MZmMHtobwQ")
  var query = PFQuery(className:"ExerciseInstance", predicate:predicate)
  </code></pre>
  
  <p>Same problem with:</p>
  
  <pre><code>var query = PFQuery(className:"ExerciseInstance")
  query.whereKey("userAccount", equalTo: "MZmMHtobwQ")
  </code></pre>
  
  <p>Any idea - what am I missing?
  Best,
  Tom</p>