Tell me more information about the aircraft called "Robinson R-22"!
select * from aircraft where aircraft = "Robinson r-22"
How many airports use this aircraft?
select * from aircraft as t1 join airport_aircraft as t2 on t1.aircraft_id = t2.aircraft_id join airport as t3 on t2.airport_id = t3.airport_id where t1.aircraft = "Robinson r-22"
What are their names, and total passengers?
select t3.airport_name, t3.total_passengers from aircraft as t1 join airport_aircraft as t2 on t1.aircraft_id = t2.aircraft_id join airport as t3 on t2.airport_id = t3.airport_id where t1.aircraft = "Robinson r-22"
What is the average total number passengers?
select avg(t3.total_passengers) from aircraft as t1 join airport_aircraft as t2 on t1.aircraft_id = t2.aircraft_id join airport as t3 on t2.airport_id = t3.airport_id where t1.aircraft = "Robinson r-22"