title: How do you properly order data from Firebase chronologically
body: <p>I'm trying to order my data from Firebase so the most recent post is at the top (like Instagram), but I just can't get it to work properly. Should I be using a server timestamp? Is there a "createdAt" field?</p>
  
  <pre><code>func getPosts() {
      POST_REF.observeEventType(.Value, withBlock: { snapshot in
          guard let posts = snapshot.value as? [String : [String : String]] else {
              print("No Posts Found")
              return
          }
  
          Post.feed?.removeAll()
          for (postID, post) in posts {
              let newPost = Post.initWithPostID(postID, postDict: post)!
              Post.feed?.append(newPost)
          }
          Post.feed? = (Post.feed?.reverse())!
          self.tableView.reloadData()
          }, withCancelBlock: { error in
              print(error.localizedDescription)
      })
  }
  </code></pre>