title: Firebase 3 issue with queryOrderedByChild
body: <p>I have an issue where the following block of code returns values correctly on a firebase 2 app, but returns nothing on a firebase 3 app. I'm guessing that the issue is caused by firebase 3 needing the uid for each of the users to be filled in in the actual query where as firebase 2 didn't need that. Code is below, and screen shot of data layout also.</p>
  
  <p>Has anyone else experienced issues like this? I know that firebase 3 is only a few weeks old so it's going to have some issues, but just hoping someone can help me out with this one.</p>
  
  <p>Thanks!</p>
  
  <pre><code>    database.queryOrderedByChild("displayName").queryEqualToValue(friendDisplayName)
        .observeSingleEventOfType(.Value, withBlock: { snapshot in
  
  })
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/ZPGXL.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/ZPGXL.png" alt="enter image description here"></a></p>