title: Parse not finding username
body: <p>In my app, Parse collects an ID number as a name at signup or login.  I want to push notifications to all users who have that ID number as follows:</p>
  
  <pre><code>@IBAction func sendAlert(sender: AnyObject) {
  
      print ("Pushing for \(theIDNumber)") //this variable is correct
      // Create our Installation query
      let pushQuery = PFInstallation.query()
      pushQuery!.whereKey("username", equalTo: (theIDNumber))
      print(pushQuery!.whereKey("username", equalTo: (theIDNumber))) // this returns a value of &lt;PFQuery: 0x15c7bc0d0&gt;
  
      // Send push notification to query
      let push = PFPush()
      push.setQuery(pushQuery) // Set our Installation query
      push.setMessage(theMessageBlank.text!) 
      push.sendPushInBackground()
      print("Message pushed")
  
  
  }
  </code></pre>
  
  <p>The result on the Parse website is that the push succeeds but is sent to zero people.  The Parse website does show that there is one person who has the requested ID number.</p>
  
  <p>I see that the ID number does not appear in the Installation pane of the Parse data browser, and I see that I am setting up a PFInstallation query.  Is that the problem?  Changing it to a PFUser.query did not help.</p>
  
  <p>Thank you,</p>
  
  <p>Eli</p>