How to organize the DataClasses.dbml file

Question

I would like to find out how people out there manage the dbml file in a more scalable manner?

Do you have just one DataClasses1.dbml and drag every table into it?

Do you have separate files for separate logical groupings, eg Accounts, HR? If so, how do you visually see the foreign key relationships when one table has links to a table in another dbml file?

Thanks.

Answer 1

Using Entity Framework (same for linq-to-sql) I like to use separate context classes for distinct parts of the database.

But what is "distinct"?

In most cases everything that is related to the core business of an application is too much interrelated for a separate context to be meaningful. But almost every application has lateral tasks like authorization, translation, auditing and so on. These are good candidates for separate contexts.

There will still be connections to the business logic though. As you probably know, you cannot join classes from separate contexts in a way that the join is translated to SQL. Only in memory. So it is useful to duplicate some entities in several contexts. So, for instance, both the business context and the authorization context will contain User entities. One context should be responsible for maintenance of the entity and the other one(s) should use it read-only.

Edit

By duplication of entities I mean that two (or more) contexts can have an entity that maps to the same table in the database. Like User. If you like, the business context could be for creating and updating users, the authorization context is (for instance) for adding roles to a specific user, without modifying the user itself.

Answer 2

Better will be to use one single DBML file for all your tables, so that you can see all your relations i.e Foreign Key etc all together..But its depends upon your requirement totally..