1/	CREATE OR REPLACE TRIGGER verification1
	BEFORE INSERT OR UPDATE ON T_TRAIN
	FOR EACH ROW
	DECLARE
	  post_time PLS_INTEGER := TO_NUMBER(TO_CHAR(:NEW.POST_TIME, 'HH24MI'));
	  arrival_time PLS_INTEGER := TO_NUMBER(TO_CHAR(:NEW.ARRIVAL_TIME, 'HH24MI'));
	  open_time_station T_STATION.OPEN_TIME%TYPE;
	  open_time_station_int PLS_INTEGER;
	  close_time_station T_STATION.CLOSE_TIME%TYPE;
	  close_time_station_int PLS_INTEGER;
	  city_post T_STATION.CITY%TYPE;
	  city_arrival T_STATION.CITY%TYPE;

	BEGIN
	  SELECT OPEN_TIME, city INTO open_time_station, city_post
	  FROM T_STATION
	  WHERE STATION_ID = :NEW.DEPARTURE_ID;

	  SELECT CLOSE_TIME, city INTO close_time_station, city_arrival
	  FROM T_STATION
	  WHERE STATION_ID = :NEW.ARRIVAL_ID;

	  open_time_station_int := TO_NUMBER(TO_CHAR(open_time_station, 'HH24MI'));
	  close_time_station_int := TO_NUMBER(TO_CHAR(close_time_station, 'HH24MI'));

	  IF(post_time < open_time_station_int) THEN
		RAISE_APPLICATION_ERROR(-20001, 'Erreur d ajout/modif' );
	  ELSIF(arrival_time > close_time_station_int) THEN
		RAISE_APPLICATION_ERROR(-20002, 'Erreur d ajout/modif');
	  END IF;
	END;