Member Avatar for bubunchan

please help me to correct my answer:

STUDYCASE:

The Following tables from part of a database held in a relational Database Management System (DBMS).

Hotel (HotelNo, HotelName, City)
Room (RoomNo, HotelNo, TypeHotel, Price)
Booking (HotelNo, GuestNo, DateFrom, DateTo, RoomNo)
Guess (GuestNo, GuestName, GuestAddress)

Note: Underlined words is primary key

and the question Like this:
LIST THE ROOM THAT ARE CURRENTLY UNOCCUPIED at the HILLTON HOTEL.

and i answer like this:

SELECT Room.RoomNo, Room.TypeHotel
FROM Room, Hotel, Booking, Guess
Where Hotel.HotelName='Hillton' AND Booking.GuestNo=Guess.GuestNo and Guess.Guestno=null;

when i try to interpret this code with insert the value of table Hotel, Room, Booking and guess. but NO OUTPUT from my code.
there is something wrong with mySQL code ?

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  • Latest Post Latest Post by varmadba
Member Avatar for varmadba 
SELECT Room.RoomNo, Room.TypeHotel
FROM Room, Hotel, Booking, Guess
WHERE Hotel.HotelName='Hillton' AND Booking.GuestNo=Guess.GuestNo AND Guess.Guestno is NULL;

Instead of Guess.Guestno=NULL; use Guess.Guestno is NULL;

Edited by varmadba because: n/a
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