DAIS_3_NO_COMPLET

CREATE OR REPLACE
FUNCTION VlozRezervaci (
                    f_idUser reservation.idUser%TYPE,
                    f_idTrainRide reservation.idTrainRide%TYPE,
                    f_coachNumber reservation.coachnumber%TYPE,
                    f_seatNumber reservation.seatnumber%TYPE
                    ) RETURN VARCHAR2 AS
CURSOR reservationCursor IS SELECT * FROM Reservation;
BEGIN
FOR resCurs IN reservationCursor LOOP
  IF (f_coachNumber = resCurs.coachNumber AND
      f_idTrainRide = resCurs.idTrainRide AND
      f_coachNumber = resCurs.coachNumber AND
      f_seatNumber = resCurs.seatNumber) THEN
      IF (resCurs.canceledDate = NULL) THEN
        UPDATE reservation SET resCurs.coachNumber = f_coachNumber;
        RETURN 'OK';
      ELSE
        RETURN 'FAILED';
      END IF;
  ELSE
  INSERT INTO RESERVATION (idUser, idTrainRide, coachNumber, seatNumber) VALUES (f_idUser, f_idTrainRide, f_coachNumber, f_seatNumber);
  RETURN 'OK';
  END IF;
END LOOP;
END;