Is a Candidate Key a form of Business Rule? Are Referential Integrity rules a form of Business Rules?
At the moment, I am using VFP to design the user services, business services and data services layers of my applications. I want to make sure that my design allows me the greatest possible independence of databases and programming languages. I would like to be able to move the data to Microsoft SQL Server, Oracle or almost any other back-end database. I would like the ability to design a front end using Visual Basic, ASP or almost any other development system.
I would appreciate advice on whether to enforce the uniqueness of key fields or expressions in a 3 (or more) tier structure in the data services or the business services layer. Similarly, should Referential Integrity be maintained in the data services or business services layer?
James McIlwrath
Datasmith Ltd.
250 Webb Drive, Suite 1206
Mississauga, ON L5B 3Z4
Canada
Phone:(905) 566-0766
Fax:(905) 566-4547
E-mail:
jmci@rogers.com