SQL query to search for room availability

Question

The follow tables I have are:

 CUSTOMERS (CustomerID, firstname, surname etc)
 ROOMS (RoomID, RoomType, Description)
 BOOKING (BookingID, CustomerID, Arriva         


        

Answer 1

this query list all rooms and for each room shows if it is available within [Arrival , Departure] dates

SELECT 
    RoomType,
    case when NOT EXISTS (SELECT RoomID 
                  FROM ROOMS_BOOKED rb 
                  JOIN BOOKING b on b.BookingID = rb.BookingID
                  WHERE rb.RoomID = r.Id 
                    and ArrivalDate < 'param Departure Date here'
                    and DepartureDate > 'param Arrival Date here')
        then 1 else 0 end IsAvailable
FROM ROOMS r