DAIS_COMPLET_2_BETTER_VERSION

CREATE OR REPLACE
FUNCTION CheckStaff(
              p_idUser "User".idUser%TYPE,
              p_idTrainRide TrainRide.idTrainRide%TYPE
              ) RETURN BOOLEAN AS
help INT;
CURSOR boolcurs IS SELECT * FROM Reservation WHERE idUser = p_idUser AND idTrainRide = p_idTrainRide;
CURSOR crewcurs IS SELECT * FROM TrainCrew WHERE idTrainRide = p_idTrainRide;
BEGIN
  FOR cur IN boolcurs LOOP
    FOR crew IN crewcurs LOOP
      IF (cur.confirm = crew.idStaff) THEN
        help := 1;
        EXIT;
       ELSE
        help := 0;
      END IF;
    END LOOP;
    IF (help=0) THEN
      EXIT;
    END IF;
  END LOOP;

  IF (help = 0) THEN
    RETURN FALSE;
  ELSE
    RETURN TRUE;
  END IF;
END;