Anyone who has been developing on the Microsoft platform for the last several years knows the drill: every few years, there’s a new database access technology. There was ODBC; then DAO and RDO; OLEDB, ADO, and ADO.NET; LINQ to SQL; and now Entity Framework! In many ways, this progression of technologies has been confusing, but in other ways it’s wonderfully refreshing to see this field evolve from simple open connectivity to componentized connectivity, to disconnected access in a managed environment, to friction-less access syntax, and finally to conceptual modeling.

It’s the conceptual modeling that is the defining feature of Entity Framework and is at the heart of this book. Entity Framework builds upon the previous data access paradigms providing an environment that supports rich, real-world domain level modeling. We can now think of and program against realworld things such as orders and customers, and leverage concepts such as inheritance to reason about things in our domain and not just rows and columns.

There is no question that Entity Framework is the future of data access for the Microsoft platform. The first release in August of 2008 was widely considered a good first step. Now, more than year later, this new release of Entity Framework (often called EF 4.0) as part of the newly released Visual Studio 2010 and .NET 4.0 has matured into a full function data access technology ready for production use in both green field and legacy applications.

The concepts and patterns you will learn as you use the recipes in this book will serve you well into the future as Microsoft continues to evolve Entity Framework in the years to come.