Firebase Realtime Database delete specific user

Question

I wish to delete specific user with phone number X from my DB. And insted my code deletes all of them.

Here is my DB:

Code:

    private static void deleteUser(final Context context, final String phoneNumber) {

        DatabaseReference databaseReference = FirebaseDatabase.getInstance().getReference("users");
        Query usersQuery = databaseReference.orderByChild("phone").equalTo(phoneNumber);

        usersQuery.addListenerForSingleValueEvent(new ValueEventListener() {
            @Override
            public void onDataChange(DataSnapshot dataSnapshot) {

                dataSnapshot.getRef().removeValue().addOnCompleteListener(new OnCompleteListener<Void>() {
                    @Override
                    public void onComplete(@NonNull Task<Void> task) {

                        Log.d(TAG, "Deleted");

                    }
                });

            }

            @Override
            public void onCancelled(DatabaseError databaseError) {
                Log.d(TAG, "onCancelled", databaseError.toException());
            }


        });
    }

Answer 1

Maybe it is not clear with my comment, so I am putting this as an answer, the full code that should not be having the problem you're facing, should look something like this:

usersQuery.addListenerForSingleValueEvent(new ValueEventListener() {
            @Override
            public void onDataChange(DataSnapshot dataSnapshot) {

                  for (DataSnapshot ds: dataSnapshot.getChildren()) {                
                         ds.getRef().removeValue().addOnCompleteListener(new OnCompleteListener<Void>() {
                            @Override
                            public void onComplete(@NonNull Task<Void> task) {

                                 Log.d(TAG, "Deleted");

                            }
                         });

                  }
            }

            @Override
            public void onCancelled(DatabaseError databaseError) {
                Log.d(TAG, "onCancelled", databaseError.toException());
            }


        });

That's because you're using a singleValueEventListener . If the query matches multiple children, it returns a list of all those children.

Even if there's only a single matches child, it's still a list of one. And since you're calling getRef() on that list, you get the key of the location where you ran the query.