How do I enforce data integrity rules in my database?

Question

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

Answer 1

You can set up some insert/update triggers. Just check if these fields are null or notnull, and reject insert/update operation if needed. This is a good solution if you want to store all the data in the same table.

You can create also create a unique table for each classes as well.