Designing a new application in asp.net 4 I have to make a decision how to use a MS SQL Membership API along with my own data in the MS SQL data base. Firstly I need to store and access user profile data in more flexible manner then the Profile provider supports. Secondly I would like to link other user related information (e.g. Orders).
No matter where you store your aspnetdb tables (in the separate data base or in the same data base with your data), the problem stays how to keep your data synchronized.
After a research I see the following relevant options:
1. Foreign key UserId from asp_Users (suggested in this tutorial).
2. No foreign key - use transactions (suggested here).
3. No foreign key - use customized AccountController (whatever it is, suggested here).
4. Additional table which links Membership UserId (uid) with custom UserId (int).
5. ...
On the one hand I like the first solution as it is quite straightforward and is suggested in an official asp.net tutorial.
On the other hand opponents note quite reasonably that using foreign keys breaks the general idea of providers which are supposed to help separating concerns and to be interchangeable. But unfortunately they do not go much into implementation details so it is not really easy to estimate those suggestions in terms of relevance and ease of implementation.
So what is the best option to approach this? Furthermore how would the implementation look like? Would it be enough to use just additional ADO.NET or LINQ etc code or is it worth implementing a custom Membership and/or Profile Provider?
Thank you in advance.