firebase - How to tell which descendants are changed with on("child_changed")

Question

For example, I have following database structure:

/ 
+ users
  + 1
    + items
      + -xxx: "hello"
  + 2
    + items

Then;

var usersRef = new Firebase("https://mydb.firebaseio.com/users");
usersRef.on("child_changed", function(snapshot) {
  utils.debug(JSON.stringify(snapshot.exportVal()));
});

If a value, "world", is pushed to "/users/1/items", I may get:

{"items": {"-xxx": "hello", "-yyy": "world"}}

So, how to tell which one is changed?

I need to on("child_added") every single ref to "/users/$id/items"?

NOTE: I'm trying to write an admin process in node.js.

Answer 1

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