public static MovieRecord GetByID(int id)
        {
            using (NpgsqlConnection conn = new NpgsqlConnection(ConnectionString))
            {
                conn.Open();
                using (var command = new NpgsqlCommand("SELECT * FROM movies WHERE movie_id = @ID", conn))
                {
                    command.Parameters.AddWithValue("@ID", id);

                    NpgsqlDataReader reader = command.ExecuteReader();
                    if (reader.HasRows)
                    {
                        reader.Read();
                        double pp     = Convert.ToDouble(reader["price"]);
                        var    copies = CopyRecord.GetByMovieId(id);
                        return(new MovieRecord(id, (string)reader["title"], (int)reader["year"], pp, copies));
                    }

                    else
                    {
                        return(null);
                    }
                }
            }
        }