เครื่องบินที่เล็กที่สุดที่สามารถบินจากพิตส์เบิร์กถึงบัลติมอร์คือเครื่องบินลำใดที่เล็กที่สุดไม่จำเป็นต้องใช้ตารางทั้งหมด
what is the smallest aircraft available to fly on from PITTSBURGH to BALTIMOREIt is not neccessary to use all the tables.
 aircraft:  aircraft_code [ varchar]  aircraft_description [ varchar]  manufacturer [ varchar]  basic_type [ varchar]  engines [ int]  propulsion [ varchar]  wide_body [ varchar]  wing_span [ int]  length [ int]  weight [ int]  capacity [ int]  pay_load [ int]  cruising_speed [ int]  range_miles [ int]  pressurized [ varchar] 
SELECT DISTINCT aircraft.aircraft_code FROM aircraft, airport_service AS AIRPORT_SERVICE_0, airport_service AS AIRPORT_SERVICE_1, city AS CITY_0, city AS CITY_1, equipment_sequence, flight WHERE aircraft.capacity = (SELECT MIN(AIRCRAFTalias1.capacity) FROM aircraft AS AIRCRAFTalias1, airport_service AS AIRPORT_SERVICEalias2, airport_service AS AIRPORT_SERVICEalias3, city AS CITYalias2, city AS CITYalias3, equipment_sequence AS EQUIPMENT_SEQUENCEalias1, flight AS FLIGHTalias1 WHERE CITYalias2.city_code = AIRPORT_SERVICEalias2.city_code AND CITYalias2.city_name = 'PITTSBURGH' AND CITYalias3.city_code = AIRPORT_SERVICEalias3.city_code AND CITYalias3.city_name = 'BALTIMORE' AND EQUIPMENT_SEQUENCEalias1.aircraft_code = AIRCRAFTalias1.aircraft_code AND FLIGHTalias1.aircraft_code_sequence = EQUIPMENT_SEQUENCEalias1.aircraft_code_sequence AND FLIGHTalias1.from_airport = AIRPORT_SERVICEalias2.airport_code AND FLIGHTalias1.to_airport = AIRPORT_SERVICEalias3.airport_code) AND CITY_0.city_code = AIRPORT_SERVICE_0.city_code AND CITY_0.city_name = 'PITTSBURGH' AND CITY_1.city_code = AIRPORT_SERVICE_1.city_code AND CITY_1.city_name = 'BALTIMORE' AND equipment_sequence.aircraft_code = aircraft.aircraft_code AND flight.aircraft_code_sequence = equipment_sequence.aircraft_code_sequence AND flight.from_airport = AIRPORT_SERVICE_0.airport_code AND flight.to_airport = AIRPORT_SERVICE_1.airport_code