Oct 2 2007 * Brad Tutterow. VS 2008.NET 3.5LINQ Entity Framework The ADO.NET Entity Framework is...

Oct 2 2007 * Brad Tutterow

The ADO.NET Entity Framework is part of Microsoft’s next generation of .NET technologies.

It is intended to make it easier and more effective for object-oriented applications to work with data.

04/20/23 Daugherty Business Solutions * Brad Tutterow

Originally intended to be part of the Visual Studio 2008 Release

Now scheduled for “later”.

Entity Framework is currently Beta 2

Entity Framework Tools are currently CTP


Inherit differences between data expression in a relational database and the same data expressed in an object-oriented application.

04/20/23Daugherty Business Solutions * Brad Tutterow

• Almost any business application today has to speak to a relational database.

• This involves the usual suspects of tables with foreign keys, a smattering of views, and generally a gob of stored procedures.


Applications themselves are written in a completely different world.

The same data that lives in the relational database is represented entirely differently in the application.


The result of this “impedance mismatch” is that developers devote a lot of time and energy writing code to translate between how the database likes to see data and how the application likes to see data.


Hibernate (Java) Enterprise Objects Framework

(Mac OS) NHibernate (.NET) LINQ to SQL (Visual Studio 2008) And many, many, more …


The ADO.NET Entity Framework seeks to remedy the problem by providing a layer of abstraction between the logical data model and the application domain.


Closer to the application problem space

Better suited for object oriented programming

Supports Inheritance Supports complex

types Relationships are more

meaningful to the application


The tools and technology that developers will interact with when using the ADO.NET Entity Framework


A gob of XML that defines Logical Data Tables,

Views, Foreign Keys Entity Objects that

Map to the Logical Data

The Mapping Between the Two


A Visual Studio Designer that protects developers from the XML that is the EDM


A code-generated data context created from the Entity Data Model

Responsible for managing communication between the conceptual data model and the logical data model


Code-generated class definitions for objects defined in the EDM.


How do we get data out of the fancy Entity Data Model?


A brand new SQL language to learn

Leverages the rich, object-oriented Entity Data Model Inheritance Collections Complex Types

Literal Strings – No Compiler Checking

Questionable value in embedded SQL in code


Queries the object model created against the EDM

Still string-based. No compiler checking

An ugly mix of code and eSQL statements


Full compiler checking. No wondering if the query is valid.

A fun new SQL-Like syntax

More OO-ish


Getting data out of the Entity Data Model using LINQ to Entities


The power of the Entity Data Model contrasted to a logical data model of tables and stored procedures.


Database TablesDatabase Tables Entity Data ModelEntity Data Model


Combining Two Tables into one EDM Entity


Database TablesDatabase Tables Entity Data ModelEntity Data Model


Implementing Inheritance by marking one Entity as a subclass of another


Implement Complex Types (e.g. Address)

Consume Conceptual Model with Reporting Services and other BI Tools

Create an EDM that talks to stored procedures

Use transactions, manage concurrency, cache execution plans


Database Result Desired EDM Object Manipulation

INSERT ROW Create new objectAdd object to EDM ContextUpdate Context

DELETE ROW Get instance of object from EDM ContextAsk Context to remove the objectUpdate Context

UPDATE ROW Get instance of object from EDM ContextUpdate objectUpdate Context


Oct 2 2007 * Brad Tutterow. VS 2008.NET 3.5LINQ Entity Framework The ADO.NET Entity Framework is...

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