title: Return unique/distinct values with Realm query
body: <p>I have a <code>Message/RLMObject</code> model that has a <code>NSString *jabberID</code> property/row and I want to retrieve every <code>unique</code> value inside that row. </p>
  
  <p>In other word, I want to retrieve non-repeated <code>jabberID</code> values from my <code>Message</code> model. Can anyone help out figuring this? </p>
  
  <p>The way I use to do with coredata was using <code>returnsDistinctResults</code> setting on the <code>NSFetchRequest</code>.</p>