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Asked: 2026-06-05T11:34:57+00:00

I’ve learning ASP.Net and Entity Framework 4 by a practical example. To trial this,

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I’ve learning ASP.Net and Entity Framework 4 by a practical example. To trial this, I’m using the example of User sending in devices for Repair. They create an account online, add in a set of Details (address, phone, fax etc), and create the return form (RMA) online.

The concept I am struggling with, is assigning Details to the Returns. A Return has a set of Details, one for contact, delivery and billing. These can be foreign keys to the Detail table, as shown below.

The problem is, that if a User edits their Details online, it will update the Details used on the Return. This is not the desired behaviour. The Return should uses the Details which were available at the time it was created.

The question is, how do you make the entity framework create a new Detail object, instead of updating the existing one. That is if the user updates Detail 23 with a new postcode, Detail 23 is not changed, instead a new Detail is created (i.e. 45). Detail 23 is removed from the User, and the new Detail 45 is added to the User. Whilst an existing RMA using Detail 23 is unaffected, meanings if you query the RMA you get the details which were supplied at the time it was created.

If on reading this question, you think the concept is flawed, and instead the DB should be designed differently (i.e. copying Detail data to columns in RMA table, or adding in a form of composite key to Detail table to create a history of revisions). I’m happy to listen to those wise words as well.

ERD of RMA System

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  1. Editorial Team

    If you have complex data editing rules that are outside of the realm of basic CRUD, then you essentially have two choices with Entity Framework.

    1. Give up on simple data binding and build your special handling into a business rule layer that sits between your GUI and your data layer (EF).

    2. Give up the simplicity of a thin EF layer and put your special data handling rules into stored procedures and then set the CRUD procedures in your EF model to the stored procs you’ve defined.

    Either way, you are making a compromise because no ORM, EF or otherise, can accomodate both “codeless” databinding and non-trivial CRUD processing. Pick the approach that suits your project and perferences the best. Some people can’t live without databinding, some can’t live with it. Some love stored procs and others loath them.

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