db exam sql

select dest from flight f where not exists
(select LID from airline
except
select lid from flight where dest = f.dest)

select lid from flight group by lid having count(*) >
(select count(*) from flight f, airline a where f.lid = a.lid and name='Lion')

select top 1 aid from airport where aid not in
(select aid from locates l, airline a where l.lid = a.lid and name = 'Lion')
group by aid order by count(*) desc