Making two columns primary keys (composite key) when creating a table in sql server

Question

Two columns need to be primary keys and auto increment how do I go about it
Code
Create table humanresources.staffid
(
StaffID int identity (100,1) not null primary key
BranchID as StaffID+100 primary key
..........
......)
The code coul not go through.
Please I need corrections.
Thanks

Answer 1

I'm thinking 'BranchID' column could be made a foreign key instead of in a composite. Reference a primary key in (probably) "Branches" table.
* Just an idea,

Answer 2

It's a problem case study question an we are required to reference the both on a different table
Hope you understand

Answer 3

Okay thanks

Answer 4

Primary key can be only one. Probably you are seeking branchid to be unique? then just write it.
But the better way is make two different tables and set in one of the tables foreign key from other table

Answer 5

No problem then. Creat 3rd table and in different columns reference to that two id by foreign key

Answer 6

Cheers!