Chaps, your comments are interesting and perhaps make me feel not so guilty for using System.Data classes in these modern times.
I've only used netTiers and EF4 in recent years, but deep down they all run a SELECT statement, loop through the rows and move the columns into collections of objects with matching property names. In the early .NET years I wrote my own code to do that, and I know VB6 developers who are still doing it. The classes and collections returned by netTiers implemented all of the interfaces I like in System.Data. The EF4 equivalents do not seem to. So where does that leave me? I fall back to the "convenience" of System.Data and I feel guilty, but perhaps I shouldn't. Maybe no one is game to admit that EF4 is a bit immature. I've had no reply from the EF4 MSDN forum yet. I will continue to send DataSets to pick lists and grids in my UI. However, I do perform updates and deletes using the EF4 entities and context, and I'm reasonably happy with the way it works. It's tedious to eager load an entity with non-tracking, send it up to the UI, edit or delete it, then attach it back to the context and call ApplyCurrentValues on all the entities before saving it. netTiers is not regarded as a big player in the ORM field, but my experience so far is that netTiers is generally better than EF4 because its entity classes and collections are completely self-tracking, and most importantly, there is no concept of a context. The only reason I'm learning EF4 and using it is because it's "the latest greatest thing". I guess marketing does work! Greg
