Question

SQL server 2008

Hello

here is my query which returns the result

SELECT * FROM Rooms
WHERE RoomID in 
(SELECT t1.RoomId FROM 
(Rooms t1 INNER JOIN 
(SELECT RoomID, SUM(quantity) AS QTY FROM Room_Item GROUP BY RoomID
HAVING SUM(Quantity) = 0) t2 ON t1.RoomID = t2.RoomID))

above written query will return me the roomid of the rooms which dosen’t have any items in it (quantity = 0),
but now i want to filter out the result by buildings,

i got the list of room for specific building as below

select roomid from rooms where buildingblockid in (select buidingblockid from buildingblock where buildigID = 1)

so my query will be

return the roomid from rooms table where allocated items are 0 and filter out room by building number = 1

tables structure is as below – ONLY ESSENTIAL FIELDS ARE SHOWN

rooms => roomid(PK), buildingblockID(FK), roomname
room_item => roomitemid(PK), roomid(FK), itemid(FK), quantity
item => itemid(PK), itemname
buildingblock => buildingblockid(PK), buildingID(FK)
building => buildingID(PK), buildingName

Answer 1

You could create derived table to find rooms having no items, and join it to buildingWiseRoom to filter building one.

select buildingWiseRoom.roomID
from buildingWiseRoom
inner join
(
   select RoomID
     from Room_Item 
    group by RoomID 
   having SUM(Quantity) = 0
) itemlessRooms
  on buildingWiseRoom.roomID = itemlessRooms.roomID
where buildingWiseRoom.buildingID = 1

UPDATE as table structure changed:

select rooms.roomID
from rooms
inner join buildingblock 
   on rooms.buildingblockID = buildingblock.buildingblockID
inner join
(
   select RoomID
     from Room_Item 
    group by RoomID 
   having SUM(Quantity) = 0
) itemlessRooms
  on rooms.roomID = itemlessRooms.roomID
where buildingblock.buildingID = 1