How do I create a multi-column constraint in SQL Server?

Question

I know this is very simple, but how do I do this in plain SQL?

Mark Byers · Accepted Answer · 2009-12-03 19:54:29Z

3

For a unique constraint during table creation:

CREATE TABLE T1 (
    Col1 int NOT NULL,
    Col2 int NOT NULL,
    UNIQUE (Col1, Col2)
)

After table creation:

ALTER TABLE T1 ADD UNIQUE (Col1, Col2)

answered Dec 3, 2009 at 19:54

Mark Byers

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Comments

UserControl · Accepted Answer · 2009-12-03 19:56:25Z

0

Are you talking about check constraints?

alter table MyTable add constraint CC_Dates check (FromDate < ToDate)

answered Dec 3, 2009 at 19:56

UserControl

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