If ID fields are of charchter type, you can concatenate them directly. Otherwise you'll have to convert them to chrackter type before concatination using CAST or CONVER functions.

Select * from Test where ID + ID2 + ID3 + ID4 not in (Select distinct ID + ID2 + ID3 + ID4 from site)

>Hi,
> I want to do an update of my database to add fields only if the set of field (4 field ) are not found . With one field you can do
> Select * from Test where ID not in (Select distinct ID from site) and it would return all ID that are not in the table.. How do you that with 4 fields (a sort of Select * from Test where ID,ID2,ID3,ID4 not in (Select distinct ID,ID2,ID3,ID4 from site). None of these field are primary key though. (one table is only a list of all existing element and the other one the actual table I want to update, but the primary key for this table is a automatically assigned number).