hi there,

On page 514 is a table which compares the ordinary sql to the Linq to entities.
now on page 515 there is the 100:1 difference partially explained.

Now in distributed designs I have to follow also the recommendations at page 513.
-Create a new Context for each web service call(being stateless)
-Add changes to the store in batches.

1)this would mean I would have a first call to the Web service which fetches all the data required in the Client.
2)the changes have to be collected until a predefined Time point at which all the changes are written back by calling a web service method with a list of CUD operations on some entities

Hmm point 1 would mean that the user would have to wait a long time before its data appears.
point 2 is prone to crashes if the client crashes before the mass of collected changes are applied.

somehow I have the feeling that EF is not appropriate for distributed designswith 3 Layers.One could use EntityBag approaches but the Data transfer objects are not persistent ignorant.

Anyone some comment? am I wrong somewhere?

thanks
David

David,

<<somehow I have the feeling that EF is not appropriate for distributed designswith 3 Layers.One could use EntityBag approaches but the Data transfer objects are not persistent ignorant.>>

You're correct that EF v1 isn't appropriate for three-tier systems if you need POCOs (for persistence ignorance). The ADO.NET team might add n-tier with POCO features to forthcoming v2, but the have been waffling on this issue lately.

--rj

Thank you very much,

This affirmed my suspicions. I hope desparately that this will come with version 2....
But v2 will not be available before october 2009?!

I had a look at several other ORM tools for .NET.
Telerik Open Access, .NET DataObjects, genome-e, Nhibernate.
Only OpenAccess seems to be usable for .NET 3.5 environments.
But none of them convinced me entirely.
so I guess I will fallback to Datasets with Linq To Dataset filling POCOs for our Businesslayer!

You might want to check out Frans Bouma's LLBLGen Pro O/RM, which supports n-tier but not POCO.

Another obvious O/RM candidate is NHibernate, although the learning curve is quite steep.

--rj

So that was it for EF ...
My conclusions and thoughts are here:
http://www.richter-web.info/Wordpress/?p=39

If someone finds that I am mistaken, please enlight me-making a comment ....