public static UplataUcenika GetUplataByUcenikId(SqlConnection conn, int id)
        {
            UplataUcenika uplUc = null;

            try
            {
                string query = "SELECT uplata_id, ucenik_id " +
                               "FROM uplata_ucenika " +
                               "WHERE id=" + id;
                SqlCommand cmd = new SqlCommand(query, conn);

                SqlDataReader r = cmd.ExecuteReader();
                if (r.Read())
                {
                    int uplataId = (int)r["uplata_id"];
                    int ucenikId = (int)r["ucenik_id"];

                    Uplata uplata = UplataDAO.GetUplataById(Program.conn, uplataId);
                    Ucenik ucenik = UcenikDAO.GetUcenikById(Program.conn, ucenikId);

                    uplUc = new UplataUcenika(id, uplata, ucenik);
                }
                r.Close();
            }
            catch (Exception e)
            {
                Console.WriteLine(e.Message);
            }
            return(uplUc);
        }
        public static void IspisiUplatuUcenikaPoId()
        {
            Console.WriteLine("Upisite id uplate ucenika: ");
            int id = Convert.ToInt32(Console.ReadLine());

            UplataUcenika uu = UplataUcenikaDAO.GetUplataByUcenikId(Program.conn, id);

            Console.WriteLine(uu.ToString());
        }