TRIGGER_checkCoach

CREATE OR REPLACE
TRIGGER checkCoach
BEFORE INSERT
ON
Reservation
FOR EACH ROW
DECLARE
myTrain train%ROWTYPE;
myTrainID INT;
coachExc EXCEPTION;
BEGIN
SELECT idTrain INTO myTrainID FROM TrainRide WHERE idTrainRide = :NEW.idTrainRide;
SELECT * INTO myTrain FROM Train WHERE idTrain = myTrainID;
  IF (:NEW.coachnumber > myTrain.coachCount) THEN
    RAISE coachExc;
  END IF;
END;