Remove Specific value From Firebase Database

Question

I want to Delete Specific value from Firebase Database following is Database which i have stored

Now, I want to Delete Fol

Answer 1

Well Thanks to all, After Modification with lots of answer and query.. This is what worked with me.

mReference.child("demo").orderByChild("fname").equalTo("John").addChildEventListener(new ChildEventListener() {
        @Override
        public void onChildAdded(DataSnapshot dataSnapshot, String s) {
            mReference.child("demo").child(dataSnapshot.getKey()).setValue(null);

            //also work
            //dataSnapshot.getRef().setValue(null);  
        }

        @Override
        public void onChildChanged(DataSnapshot dataSnapshot, String s) {

        }

        @Override
        public void onChildRemoved(DataSnapshot dataSnapshot) {

        }

        @Override
        public void onChildMoved(DataSnapshot dataSnapshot, String s) {

        }

        @Override
        public void onCancelled(DatabaseError databaseError) {

        }
    });