มีกี่เที่ยวบินที่มี CO เข้าและออกจากแอตแลนต้าไม่จำเป็นต้องใช้ตารางทั้งหมด
how many flights has CO into and out of ATLANTAIt is not neccessary to use all the tables.
 month:  month_number [ int]  month_name [ text] 
SELECT COUNT(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, flight WHERE ((flight.from_airport = AIRPORT_SERVICE_0.airport_code AND CITY_0.city_code = AIRPORT_SERVICE_0.city_code AND CITY_0.city_name = 'ATLANTA') OR (flight.to_airport = AIRPORT_SERVICE_1.airport_code AND CITY_1.city_code = AIRPORT_SERVICE_1.city_code AND CITY_1.city_name = 'ATLANTA')) AND flight.airline_code = 'CO'