Firebase offers various ways of ordering data. In this chapter we will show simple query examples.
We will use the same data from our last chapter.
Now we can order data by value for each player.
![Firebase Queries Rating Log](https://www.tutorialspoint.com/firebase/images/firebase_queries_rating_log.jpg)
We will use the same data from our last chapter.
![Firebase Queries Data](https://www.tutorialspoint.com/firebase/images/firebase_queries_data.jpg)
Order By Child
To order data by name, we can use the following code.Example
var playersRef = firebase.database().ref("players/"); playersRef.orderByChild("name").on("child_added", function(data) { console.log(data.val().name); });We will see names in alphabet order.
![Firebase Queries Order By Child](https://www.tutorialspoint.com/firebase/images/firebase_queries_order_by_child.jpg)
Order By Key
We can order data by key in similar fashion.Example
var playersRef = firebase.database().ref("players/"); playersRef.orderByKey().on("child_added", function(data) { console.log(data.key); });
![Firebase Queries Order By Key](https://www.tutorialspoint.com/firebase/images/firebase_queries_order_by_key.jpg)
Order By Value
We can also order data by value. Let's add ratings collection in Firebase.![Firebase Queries Rating Data](https://www.tutorialspoint.com/firebase/images/firebase_queries_rating_data.jpg)
Example
var ratingRef = firebase.database().ref("ratings/"); ratingRef.orderByValue().on("value", function(data) { data.forEach(function(data) { console.log("The " + data.key + " rating is " + data.val()); }); });
![Firebase Queries Rating Log](https://www.tutorialspoint.com/firebase/images/firebase_queries_rating_log.jpg)
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