Guide to Entity Framework with

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Introducing the ADO.NET 
Entity Framework
Welcome to our journey into mastering the popular data access technology from 
Microsoft named 
Entity Framework
. At the time of writing, Entity Framework 7 
hasn't been released—so we will use Entity Framework 6.x throughout this book but 
at the same time discuss what's new in Entity Framework 7.
Object Relational Mapping
(
ORM
) technology has been widely in use for over a 
decade. ORMs are used to convert data between incompatible type systems. These 
are tools that encapsulate calls to the underlying database and enable you to query 
and manipulate data using an object-oriented paradigm.
The figure that follows illustrates the persistence layer that is responsible for reading 
and manipulating data to and from the database. Now, this persistence layer can be 
your ADO.NET library, a wrapper around the ADO.NET library, or an ORM:
Presentation Layer
Business Layer
Persistence Layer
Domain
Objects
Database

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Introducing the ADO.NET Entity Framework