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
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Change tracking and identity resolution using ObjectContext


Change tracking in Entity Framework is a feature that enables you to detect and resolve conflicts that arise out of concurrent data updates on a particular entity. Such scenarios are commonly known as concurrency conflicts.

Two modes used to handle data concurrencies in a multiuser environment are:

  • Optimistic

  • Pessimistic

In the optimistic mode, the record is read but not locked. You need to check whether a record to be saved has already been modified. In essence, you need to track the changes in the data before you perform any changes.

In the pessimistic mode, the record being modified is locked from other users until the lock on the record is released. Therefore, pessimistic concurrency is not a good choice, especially when you have a large number of users accessing the application at the same point in time. For further details, please refer to http://www.asp.net/mvc/tutorials/getting-started-with-ef-using-mvc/handling-concurrency...