Book Image

Entity Framework Tutorial (Update) - Second Edition

By : Joydip Kanjilal
Book Image

Entity Framework Tutorial (Update) - Second Edition

By: Joydip Kanjilal

Overview of this book

The ADO.NET Entity Framework from Microsoft is a new ADO.NET development framework that provides a level of abstraction for data access strategies and solves the impedance mismatch issues that exist between different data models This book explores Microsoft’s Entity Framework and explains how it can used to build enterprise level applications. It will also teach you how you can work with RESTful Services and Google’s Protocol Buffers with Entity Framework and WCF. You will explore how to use Entity Framework with ASP.NET Web API and also how to consume the data exposed by Entity Framework from client applications of varying types, i.e., ASP.NET MVC, WPF and Silverlight. You will familiarize yourself with the new features and improvements introduced in Entity Framework including enhanced POCO support, template-based code generation, tooling consolidation and connection resiliency. By the end of the book, you will be able to successfully extend the new functionalities of Entity framework into your project.
Table of Contents (16 chapters)
Entity Framework Tutorial Second Edition
About the Author
About the Reviewers

Deferred, eager, and lazy loading

Eager loading refers to the process in which a query, when executed on a particular type of an entity, also loads the related entities at the same time. Lazy loading and eager loading are used for loading related entities that pertain to an entity. In the former case, the related entities are not loaded automatically along with its parent entity unless they are requested. In the latter case, the related entities are loaded automatically along with the parent entity.

To achieve eager loading in Entity Framework, you need to make use of the Include method.

Here is an example:

using (var context = new SecurityContext())
    // Load all user types and the related users
    var data = context.UserTypes
                          .Include(u => u.Users)
     // Load one user type and its related users
    var data = context.UserTypes
                        .Where(u => u.UserType == "ADUser")