I'm interested in using an object relational mapper for an existing system which is a ASP.NET client, ASP.NET Web Services middle layer, and with an Oracle back-end. All database access is done using stored procedures and no SQL is allowed in the web services. I've been investigating NHibernate, Telerik's OpenAccess ORM, and the Entity Framework. I titled this "segregated" because the database is pretty tightly controlled by the DBA's. They also control the database design and reworking the database for adequate normalization (for the object model) is pretty much out of the question. Also, allowing the tool to create any of the SQL is also out the question.
My question is: Given these constraints, which of these tools would allow the best integration for this sort of environment?
None at all.
You're not going to be using 99% of the functionality of an ORM by having everythign done in Stored Procedures.
Probably better to use a Micro ORM like ServiceStack.OrmLite, or Massive, etc...
But looking at any full fledge ORM like NH, LightSpeed, EF, is complete over-kill and will just create more complexity for 0 gain.