Creating a unique constraint for 2 columns

Question

I need to create a unique constraint based on two columns.

How do I achieve that in SQL Server 2008 Express edition?

marc_s · Accepted Answer · 2012-04-30 10:03:02Z

2

ALTER TABLE dbo.YourTable
ADD CONSTRAINT YourConstraintName UNIQUE (Column1, Column2)

answered Apr 30, 2012 at 10:03

marc_s

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Comments

njr101 · Accepted Answer · 2012-04-30 10:05:12Z

0

ALTER TABLE mytable
ADD CONSTRAINT myconstraint UNIQUE NONCLUSTERED (
  Col1,
  Col2
) ON [PRIMARY]

or if you prefer with an index:

CREATE UNIQUE NONCLUSTERED INDEX myindex ON mytable (
  Col1,
  Col2
) ON [PRIMARY]

answered Apr 30, 2012 at 10:05

njr101

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