ค้นหาแผนการเดินทางสำหรับเที่ยวบินไปกลับจาก BALTIMORE ไปยัง PITTSBURGH หลัง 20.00 น. ก่อน 22.00 น. ไม่จำเป็นต้องมีตารางทั้งหมด
find travel arrangements for a round trip flight from BALTIMORE to PITTSBURGH after 2000 o'clock pm before 2200 o'clock pmIt is not neccessary to use all the tables.
 airport_service:  city_code [ varchar]  airport_code [ varchar]  miles_distant [ int]  direction [ varchar]  minutes_distant [ int] 
SELECT DISTINCT flight.flight_id FROM airport_service AS AIRPORT_SERVICE_0, airport_service AS AIRPORT_SERVICE_1, city AS CITY_0, city AS CITY_1, fare, flight, flight_fare WHERE (((NOT fare.round_trip_cost IS NULL AND flight_fare.fare_id = fare.fare_id AND flight.departure_time < 2200 AND flight.flight_id = flight_fare.flight_id) AND flight.departure_time > 2000) AND CITY_1.city_code = AIRPORT_SERVICE_1.city_code AND CITY_1.city_name = 'PITTSBURGH' AND flight.to_airport = AIRPORT_SERVICE_1.airport_code) AND CITY_0.city_code = AIRPORT_SERVICE_0.city_code AND CITY_0.city_name = 'BALTIMORE' AND flight.from_airport = AIRPORT_SERVICE_0.airport_code