title: Firebase : How to add new attribute in existing table
body: <p>I am working on a project in swift and having firebase as backend for managing data.</p>
  
  <pre><code>FirebaseApp.configure()
  Database.database().isPersistenceEnabled = true
  </code></pre>
  
  <p>This is what I have set in app delegate file. Now in my chat module, I have added message information in firebase database through below code.</p>
  
  <pre><code>    let messageData = ["text": text, "senderId": senderId, "senderName": senderDisplayName, "MediaType": "TEXT"]
      self.messageSentRef?.child("Messages").childByAutoId().setValue(messageData)
  </code></pre>
  
  <p>Now I want to add one new attribute named TimeStamp in messages table.</p>
  
  <p>Anyone can help me how to do that?</p>