Unique constraint on multiple columns

Question

CREATE TABLE [dbo].[user](
        [userID] [int] IDENTITY(1,1) NOT NULL,
        [fcode] [int] NULL,
        [scode] [int] NULL,
        [dcode] [int] NULL,
                


        

Answer 1

This can also be done in the GUI. Here's an example adding a multi-column unique constraint to an existing table.

1. Under the table, right click Indexes->Click/hover New Index->Click Non-Clustered Index...

2. A default Index name will be given but you may want to change it. Check the Unique checkbox and click Add... button

3. Check the columns you want included

Click OK in each window and you're done.