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    <p>If you want to use Entity Framework you should use ObjectContext, not DataContext as this is a base class from Linq-To-Sql.</p> <p>When you create ADO.NET Entity Data Model , Visual Studio generates (after you complete a generate model from database wizard or use the designer), a class that is derived from ObjectContext that has a default connection string (that you choose at the wizard). <a href="http://blogs.msdn.com/b/adonet/archive/2010/07/19/absolue-beginners-guide-to-entity-framework.aspx" rel="nofollow">Here</a> you can see a nice tutorial from ADO.NET team how to start using the EF. </p> <p>You are not supposed to use ObjectContext directly, at least not without manually creating the metadata files and pointing to them in your connection string (Never seen DataContext class being used directly, so if I'm wrong someone correct me) , as the wizard I mentioned above creates all sorts of mapping data - to map SQL tables/views/other stuff to Entity classes.</p> <p>if you want to supply your own connection to the class you can do it programmatically with <a href="http://msdn.microsoft.com/en-us/library/system.data.entityclient.entityconnectionstringbuilder.aspx" rel="nofollow">EntityConnectionStringBuilder</a>.</p> <p><a href="http://msdn.microsoft.com/en-us/library/bb738533.aspx" rel="nofollow">This</a> is an example how to use EntityConnectionStringBuilder it from MSDN</p> <p>Edit : I mistakenly wrote about DataContext as if it was EF base class for designer generated code. It is as <em>casperOne</em> stated a base class for Linq-To-Sql classes.</p> <p><em>Changed my answer to reflect his comment</em></p>
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    1. CO1) VS.NET doesn't generate classes that are derived from `DataContext`; `DataContext` is used by LINQ-to-SQL, not LINQ-to-Entities. VS.NET generates classes deriving from `ObjectContext`. 2) There is nothing prohibiting use of `ObjectContext` directly. What VS.NET generates is a thin layer on top of it with some convenience methods; you can easily call these methods yourself if you wish, and you don't have to use the VS.NET-generated class at all, you just have to give it a connection string which contains the metadata information (or a provide a `MetadataWorkspace` separately).
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    2. CO@casperOne 1) Thanks for the clarification. Thats a big ooops on my behalf. (I seldom look at the classes generated by both Linq-To-Sql and EF) 2) I think that while it is possible to use the base class directly in case of EF , I doubt many people would bother to write metadata files themselves.
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A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

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