ระยะทางระหว่างสนามบิน PITTSBURGH และตัวเมือง PITTSBURGH คือเท่าใด ไม่จำเป็นต้องใช้ตารางทั้งหมด
what is the distance between PITTSBURGH airport and downtown PITTSBURGHIt is not neccessary to use all the tables.
 airline:  airline_code [ varchar]  airline_name [ text]  note [ text] 
SELECT DISTINCT AIRPORT_SERVICE_0.miles_distant FROM airport, airport_service AS AIRPORT_SERVICE_0, airport_service AS AIRPORT_SERVICE_1, city AS CITY_0, city AS CITY_1 WHERE airport.airport_code = AIRPORT_SERVICE_0.airport_code AND airport.airport_code = AIRPORT_SERVICE_1.airport_code AND CITY_0.city_code = AIRPORT_SERVICE_1.city_code AND CITY_0.city_name = 'PITTSBURGH' AND CITY_1.city_code = AIRPORT_SERVICE_0.city_code AND CITY_1.city_name = 'PITTSBURGH'