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
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.
In design mode (right click table select modify) highlight both columns right click and choose set primary key
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.
create table myTable
(
Column1 int not null,
Column2 int not null
)
GO
ALTER TABLE myTable
ADD PRIMARY KEY (Column1,Column2)
GO
create table my_table (
id_part1 int not null,
id_part2 int not null,
primary key (id_part1, id_part2)
)