UNIQUE Constraints in SQL (SQL Server)

Posted by rockbala on Stack Overflow See other posts from Stack Overflow or by rockbala
Published on 2010-04-12T17:11:49Z Indexed on 2010/04/12 18:43 UTC
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unique-constraint

Why are UNIQUE Constraints needed in database ?

Can you provide any examples ?

Primary Key is UNIQUE by default... Understandable as they are referred in other tables as Foreign keys... relation is needed to connect them for rdbms platform...

but why would one refer to other columns as UNIQUE, what is benefit of doing so ?)

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