ขอค่าโดยสาร COACH ไปกลับจากบัลติมอร์ไปดัลลาสิ ไม่จำเป็นต้องใช้ตารางทั้งหมด
give me the round trip COACH fare from BALTIMORE to DALLASIt is not neccessary to use all the tables.
 restriction:  restriction_code [ text]  advance_purchase [ int]  stopovers [ text]  saturday_stay_required [ text]  minimum_stay [ int]  maximum_stay [ int]  application [ text]  no_discounts [ text] 
SELECT DISTINCT fare.fare_id FROM airport_service AS AIRPORT_SERVICE_0, airport_service AS AIRPORT_SERVICE_1, city AS CITY_0, city AS CITY_1, fare, fare_basis, flight, flight_fare WHERE (CITY_0.city_code = AIRPORT_SERVICE_0.city_code AND CITY_0.city_name = 'BALTIMORE' AND CITY_1.city_code = AIRPORT_SERVICE_1.city_code AND CITY_1.city_name = 'DALLAS' AND NOT fare.round_trip_cost IS NULL AND flight_fare.fare_id = fare.fare_id AND flight.flight_id = flight_fare.flight_id AND flight.from_airport = AIRPORT_SERVICE_0.airport_code AND flight.to_airport = AIRPORT_SERVICE_1.airport_code) AND fare_basis.class_type = 'COACH' AND fare.fare_basis_code = fare_basis.fare_basis_code