adding unique keys

[HandersonVA]

Would anyone please instruct how to prevent the duplicate record by
setting the unique keys on the ms sql server? i've been checking the
duplicate record as front-end and i found out if there is an internet
delay or some other reasons, it has a chance to store the duplicated
data into the database. so i realized it has to be done on the back-end
side.
for example, if i have three columns (office code, office id, office
section) as a unique key, how can i setup this? thanks in advance.

[SQL Menace]

create a primary key or a unique constraint

ALTER TABLE [dbo].[YourTable] WITH NOCHECK ADD
CONSTRAINT [YourTable_PK] PRIMARY KEY CLUSTERED
(
[office code],
[office id],
[office section]
) WITH FILLFACTOR = 90 ON [PRIMARY]
GO

or

ALTER TABLE dbo.YourTable ADD CONSTRAINT
IX_YourTable UNIQUE NONCLUSTERED
(
[office code],
[office id],
[office section]

) ON [PRIMARY]

Denis the SQL Menace
http://sqlservercode.blogspot.com/
HandersonVA wrote:

Would anyone please instruct how to prevent the duplicate record by
setting the unique keys on the ms sql server? i've been checking the
duplicate record as front-end and i found out if there is an internet
delay or some other reasons, it has a chance to store the duplicated
data into the database. so i realized it has to be done on the back-end
side.
for example, if i have three columns (office code, office id, office
section) as a unique key, how can i setup this? thanks in advance.