android - 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 Following Values

fname: "John"

lname: "wick"

Here, What i have try to delete specific value from Firebase..

DatabaseReference demo = mReference.child("demo").orderByValue().equalTo("John").getRef();

    demo.addListenerForSingleValueEvent(new ValueEventListener() {
        @Override
        public void onDataChange(DataSnapshot dataSnapshot) {
            dataSnapshot.getRef().removeValue();
        }

        @Override
        public void onCancelled(DatabaseError databaseError) {

        }
    });

But this will delete all values from database...

Question : How to delete that specific value??? what i have to do for that

Any help will be appreciated.

Answer 1

Waitting for answers