Guide to Entity Framework with

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This is illustrated using the self-explanatory diagram that follows:
Entity
Framework
Database
Model Object
This level of abstraction is achieved using the 
Entity Data Model
(
EDM
)—an 
extended entity relationship model. The EDM reduces the dependency of your 
domain object model on the database schema of the data store in use. We will
discuss more on this topic later in this chapter.
Developers can use the ADO.NET Entity Framework to work with domain-specific 
properties such as employee name, employee address, contact details, and so on, 
without having to be concerned with how the actual data is stored and represented in 
the underlying data store. The framework can take care of the necessary translations 
to either retrieve data from your data store or perform inserts, updates, and deletes. 
Also, Entity Framework provides support to cache data automatically by default.
Is Entity Framework just another ORM?
The ADO.NET Entity Framework is an extended ORM technology from Microsoft. 
We say it is an extended ORM because it has many additional features compared 
to a typical ORM. ORMs often use metadata and factory classes to retrieve data or 
collections of data.

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Chapter 1
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Factory classes are based on the factory design pattern and are used 
to create instances of classes without exposing the instantiation logic 
to the client.
On the contrary, using Entity Framework, you can easily map your data to
be accessible in a relational representation in the database to objects, no matter 
how the mapping is implemented. You can expose different data views to your 
application without having to change your relational schema. In essence, this allows 
the applications to have their own view of the data. The applications can even reuse 
the same views of data among themselves.
The major difference between Entity Framework and ORM tools is the EDM and the 
former's ability to query data using
strongly typed LINQ. You can even use Entity 
SQL, a T-SQL-like query language to query the EDM, to execute dynamic queries. In 
addition to what a typical ORM framework provides, the Entity Framework provides 
and supports entity inheritance, entity composition, and a flexible, loosely-coupled, 
three-tiered model consisting of the conceptual model, the mapping layer, and the 
storage model. Please refer to the 
Appendix
section for links to resources on this topic.
Entity Framework even enables you to extend the existing schema. In other words, 
you can extend the generated entity classes to create your own custom entity classes. 
You can define relationships of any kind such as one-to-one, one-to-many, and even 
many-to-many.