Question

How would you write a query to select the rooms which are booked between
2012-05-1 and 2012-11-01 from a booking database?

Answer 1

Please try the following

SELECT * from room
WHERE (roomNo, hotelNo) not in
( select roomNo, hotelNo
  from booking
  where datefrom between '2012-05-01' and '2012-11-01'
  or dateto between '2012-05-01' and '2012-11-01'
)