public void EditOrderPizza(OrderPizza OrderPizza)
        {
            // would add it if it didn't exist
            _db.Update(OrderPizza);

            // sometimes we need to do it a different way
            //var trackedMovie = _db.Movie.Find(movie.Id);
            //_db.Entry(trackedMovie).CurrentValues.SetValues(movie);
        }
        public void AddOrderPizza(int?order_id, int?pizza_id)
        {
            // LINQ: First fails by throwing exception,
            // FirstOrDefault fails to just null


            var OrderPizza = new OrderPizza
            {
                OrderId = order_id,
                PizzaId = pizza_id,
            };

            _db.Add(OrderPizza);
        }