Neil and other folks using EF4,

 

The most vital thing I need to learn in EF4 is how you are supposed to
create a strongly typed custom view of multiple tables and fill the thing.

 

In classic ADO.NET you would construct an XSD DataSet with the columns you
want, then write a SELECT with JOINs to fill it. In netTiers the process is
nearly the same, you write the View then the classes and methods are
generated, but it's all plain ADO.NET under the covers.

 

I can't find the equivalent of this in EF4. I created a new Entity in the
designer with the combined columns of different tables I'm joining,
expecting this to represent my view. However, after hours of suffering I
can't create such a thing because of errors like these:

 

EntitySets 'MainLists' and 'Instance' are both mapped to table 'Instance'.
Their primary keys may collide.

Must specify mapping for all key properties (MainLists.InstId) of the
EntitySet MainLists.

 

There are hundreds of reports of people pleading about how to overcome these
sorts of edmx problems, and no clear answers. I have joined the ranks of the
bewildered and I have corrupted dozens of edmx files attempting to manually
edit them as some suggest. So I'm wondering if I'm actually trying to do the
wrong thing, pushing EF4 to do something it doesn't do due to a
misconception on my part.

 

Does anyone know how to make a strongly typed custom view and fill it in
EF4?

 

I'm pleased to see that there are other people posting EF4 questions on the
web and asking things like "why is it so hard?"

 

Greg

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