Since your question is really about WCF RIA Services and stored procedures and is not specifically connected with any Telerik control, my suggestion is to post it on the WCF RIA Services forums and I am sure that you will get a lot of feedback there.
In other words, using RadDomainDataSource you can do this in absolutely the same way as you would do it with the stock WCF RIA DomainDataSource. There is no difference.
Here is what I found after a quick Google search. Anyway, my suggestion is to ask the guys on the WCF RIA Services forums what is the best way to use WCF RIA Services with Stored Procedures.
Thank you for your understanding.
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