Introducing .NET 4.0: with Visual Studio 2010

8.4. EF 101

Many developers may be unfamiliar with EF, as it was released in between VS2008 and VS2010, and others may have heard bad things about it (not all of which are true). Let's take a quick look at how to work with EF before looking at the new features in EF4.

8.4.1. Entity Data Model

All EF applications contain an entity data model (EDM) that describes the objects in the underlying data source. The EDM can be further divided into three layers:

• Conceptual model (the view your users see)

• Storage model (how data is actually stored)

• Mapping model (links the conceptual and storage models)

EDMs are stored as XML and are composed of three main sections (which link to the three conceptual layers already described):

• CSDL (Conceptual Schema Definition ...