在MS SQL Server中加入多个表

Question

![expected result that i want ] 1

select 
bd.BuildingID , 
bd.[Building Description] , 
fl.Floor , 
rm.Room,
rm.[Room Description],
rm.[Room Type],
asse.AssetName,
cmp.ComponentName
from Buildings bd 
join Floors fl
on bd.BLDID = fl.BLDID
join Rooms rm
on fl.FLID = rm.FLID
join Assets asse 
join Components cmp
on cmp.AssetID=asse.AssetID;

I am trying to join multiple tables in ms sql server. I have 5 tables:

1. buildings
2. floors
3. rooms
4. assets
5. components

I want records from multiple tables.

• I joined bd.BLDID = fl.BLDID as I want bd.BuildingID and bd.[Building Description] and both of them have common BLID .
• I joined fl.FLID = rm.FLID as I want rm.Room , rm.[Room Description] , and rm.[Room_Type]
• I want to join asset and components as well as I want asse.AssetName and cmp.ComponentName (both tables have a common AssetID )

I know the query above won't work because of the last 2 lines.

Can anyone suggest how this join could be accomplished?

Answer 1

Per comments, we'd need to know which fields were available in your database to fully answer your question.

At a guess, I'd say assets are likely held in a room, so there's likely to be a RoomId value (or RMID given the naming convention that seems to be in place) on the assets.

If that's the case, something like this should work:

select bd.BuildingID 
, bd.[Building Description] 
, fl.Floor 
, rm.Room
, rm.[Room Description]
, rm.[Room Type]
, asse.AssetName
, cmp.ComponentName
from Buildings bd 
inner join Floors fl
on bd.BLDID = fl.BLDID
inner join Rooms rm
on fl.FLID = rm.FLID
inner join Assets asse

on asse.RMID = rm.RMID --added this line

inner join Components cmp
on cmp.AssetID=asse.AssetID;