Check if child exists in firebase

Question

Android Java Firebase:

 DatabaseReference root = FirebaseDatabase.getInstance().getReference();
    DatabaseReference users = root.child("Users");
users.addListenerForSingleValueEvent(new ValueEventListener() {
            @Override
            public void onDataChange(DataSnapshot snapshot) {
                if (snapshot.childExists("name")) {
                    // run some code
                }
            }

            @Override
            public void onCancelled(DatabaseError databaseError) {

            }
        });

This is my code, but childexists is not a valid working method. What is a way to check? If there is something similar can I just fix it?

Possible duplicate of - http://stackoverflow.com/questions/37397205/google-firebase-check-if-child-exists — saurav, Oct 16 '16 at 04:54

score 3 · Answer 1 · answered Oct 16 '16 at 06:16

3

Either use hasChild():

public void onDataChange(DataSnapshot snapshot) {
    if (snapshot.hasChild("name")) {
        // run some code
    }
}

Or child().exists():

public void onDataChange(DataSnapshot snapshot) {
    if (snapshot.child("name").exists()) {
        // run some code
    }
}

answered Oct 16 '16 at 06:16

Frank van Puffelen

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Im not aware how Firebase works in this regard, does the OnValueListener actually grab all the data from the database? Just wondering if this would be the right solution for a database with thousands of user entries etc. – James Heald Sep 30 '17 at 14:31

Check if child exists in firebase

1 Answers1