how do I make a composite key with SQL Server Management Studio?

Question

how do I make a composite key with SQL Server Management Studio?

I want two INT columns to form the identity (unique) for a table

Answer 1

In design mode (right click table select modify) highlight both columns right click and choose set primary key

Answer 2

Highlight both rows in the table design view and click on the key icon, they will now be a composite primary key.

I'm not sure of your question, but only one column per table may be an IDENTITY column, not both.

Answer 3

create table my_table (
    id_part1 int not null,
    id_part2 int not null,
    primary key (id_part1, id_part2)
)

Answer 4

here is some code to do it:

-- Sample Table
create table myTable 
(
    Column1 int not null,
    Column2 int not null
)
GO

-- Add Constraint
ALTER TABLE myTable
    ADD CONSTRAINT pk_myConstraint PRIMARY KEY (Column1,Column2)
GO

I added the constraint as a separate statement because I presume your table has already been created.