How many airlines are there?
select count ( * ) from airlines
What's the least number of routes that an airline runs?
select count ( * ) from airlines as t1 join routes as t2 on t1.alid = t2.alid group by t1.name order by count ( * ) asc limit 1
how about the most number of routes that an airline runs?
select count ( * ) from airlines as t1 join routes as t2 on t1.alid = t2.alid group by t1.name order by count ( * ) desc limit 1
What is the name of that airline?
select t1.name from airlines as t1 join routes as t2 on t1.alid = t2.alid group by t1.name order by count ( * ) desc limit 1
What country does Ryanair belong to?
select country from airlines where name = "Ryanair"