Book Image

Entity Framework Tutorial

By : Joydip Kanjilal
Book Image

Entity Framework Tutorial

By: Joydip Kanjilal

Overview of this book

<p>The ADO.NET Entity Framework is a new way to build the data access layer of your Windows or web applications. It's an Object Relational Mapping (ORM) technology that makes it easy to tie together the data in your database with the objects in your applications, by abstracting the object model of an application from its relational or logical model.<br /><br />This clear and concise book gets you started with the Entity Framework and carefully gives you the skills to speed up your application development by constructing a better data access layer. It shows you how to get the most from the ADO.NET Entity Framework to perform CRUD operations with complex data in your applications.<br /><br />This tutorial starts out with the basics of the Entity Framework, showing plenty of examples to get you started using it in your own code. You will learn how to create an Entity Data Model, and then take this further with Entity types. You will also learn about the Entity Client data provider, learn how to create statements in Entity SQL, and get to grips with ADO.NET Data Services, also known as Project Astoria.</p>
Table of Contents (13 chapters)
Entity Framework Tutorial
Credits
About the Author
About the Reviewer
Preface

Exploring the Payroll Entity Data Model


The ADO.NET Entity Data Model allows the application to have its own view of the application's data.

Here again is the design view of the Payroll EDM we created in Chapter 2:

Note that the relationships and the respective fields are displayed along with their multiplicity. You can also see the Scalar and NavigationProperties. While the Scalar Properties section lists the attributes or the fields of the Entity, the NavigationProperties are those that denote the associations of a particular Entity with other entities. As an example, the Employee entity uses the Department and the Salary entities to relate its foreign keys DepartmentID and SalaryID respectively. Therefore, you can see that the Department and Salary entities are listed in the NavigationProperties section of the Employee entity.

The Mapping Details Window

Now we will take a look at the mappings details. That is, how the properties of the entities are mapped to the underlying database.

To...