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These docs are for version 2.4.2 and below of the Javascript SDK. Go to our current docs, or see our Web migration guide.

Version 2.4.2Changelog

Query.startAt()

Using startAt(), endAt(), and equalTo() allows us to choose arbitrary starting and ending points for our queries. For example, using our sample Firebase of dinosaur facts, we can find all dinosaurs that are at least three meters tall by combining orderByChild() and startAt():

var ref = new Firebase("https://dinosaur-facts.firebaseio.com/dinosaurs");
ref.orderByChild("height").startAt(3).on("child_added", function(snapshot) {
  console.log(snapshot.key())
});

The starting point is inclusive, so children with exactly the specified value will be included in the query. The optional key argument can be used to further limit the range of the query. If it is specified, then children that have exactly the specified value must also have a key name greater than or equal to the specified key.

You can read more about startAt() in our querying data documentation.