How do I enforce data integrity rules in my database?

Question

I\'m designing this collection of classes and abstract (MustInherit) classes…

Answer 1

Personally I always insist on putting data integrity code on the table itself either via a trigger or a check constraint. The reason why is that you cannot guarantee that only the user interface will update insert or delete records. Nor can you guarantee that someone might not write a second sp to get around the constraints in the orginal sp without understanding the actual data integrity rules or even write it because he or she is unaware of the existence of the sp with the rules. Tables are often affected by DTS or SSIS packages, dynamic queries from the user interface or through Query analyzer or the query window, or even by scheduled jobs that run code. If you do not put the data integrity code at the table level, sooner or later your data will not have integrity.