Where does the business logic go in WCF Dat service using entity framework?
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I was looking at how you can create a WCF data service around an entity framework context and you can consume it as an EF context as well.

[Creating an OData API for StackOverflow including XML and JSON in 30 minutes][1]

  [1]: http://www.hanselman.com/blog/CreatingAnODataAPIForStackOverflowIncludingXMLAndJSONIn30Minutes.aspx

I really just started looking at this, but I was wondering where would the business logic go? As a service I would expect that you couldn't just freely add/delete etc without it having some validation.

If I wrote an MVC app to consume this service, how would I best implement business logic. Not simple property level validation that you could do with attributes, but more complex stuff that needs to check the data store first etc.