Posted by Erland Sommarskog on 11/23/07 22:18

Fritz Franz (fritzfranz24@hotmail.com) writes:
> OK, I understand. Yes, you ar right, the design of DB is not normalized
> correctly. But for some reasons we decided to do it this way. It is not
> that important to have the FK defined in the DB, the applications will
> ensure the integrity of the data.

An application cannot ensure data integrity. An application can add its
own checks, and sometimes it has to make messages user-friendly. But it
cannot ensure data integrity, because sooner or later someone will run
an UPDATE/INSERT/DELETE directly from SQL when the application is not
watching.


--
Erland Sommarskog, SQL Server MVP, esquel@sommarskog.se

Books Online for SQL Server 2005 at
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