We generated a query whose InfoProvider is 0Vendor. Run the query, find the last row shows # as Vendor number and the description of it is "Not Assigned".
We go to RSA1 -> Goto InfoProvider page -> Locate 0Vendor -> Right click and select Manage to check this 0Vendor master data content, find that most of fields of 1st record are null (including vendor number). Maybe that's the reason that when we run the query, the last row shows # for vendor number and the description is "Not Assigned"? And also we find if we check other master data, 1st records seems to be null as well. That's the way BW was desinged? Wonder why when checking contents of master data, 1st record is null?