Foreword

Chris Sells, SQL Server division, Microsoft Corporation

I first met Julie Lerman (rhymes with German) while she was visiting the Microsoft campus for a Software Design Review (SDR). An SDR is an event where we invite customers we trust to be representative of a much larger crowd. In this particular case, I was new to the SQL Server division and trying hard to catch up on the raft of technologies Microsoft shipped in the data space for developers. Julie, on the other hand, was a seasoned veteran and not only knew the answers to all of my Entity Framework questions but had already written a book on the topic. That book, Programming Entity Framework, was the first edition of the book youre now holding in your hands. Or, if you are a .NET programmer, you know it simply as THE book on EF.

As the months went on, I ran into Julie more and more. She was researching the second edition of her famous EF book. And by researching, I mean pointing out our mistakes. Julie was not only invaluable for teaching customers the real-world ins and outs of EF, she had a way of asking questions about alphas and betas that made us rethink what we were doing in many cases to improve the version of EF that ships with .NET 4 as well as the supporting functionality in Visual Studio 2010. And she was so well respected because of her first EF book that anything she said received extra attention from the EF team in ways I dont see for many senior architects, let alone lowly program managers. Julie had become an ad hoc member of the EF team itself.

My most recent encounter with Julie was by far the most fun. At a talk at the 2010 TechEd in New Orleans, I had the privilege of being Julies code monkey, which meant mostly that I fetched her coffee, carried her bags, and wrote her code while she entertained and educated a packed room. In 60 minutes, she did a tour de force tour through nearly all the new features in EF 4.0, driving me through one complete demo every 4 minutes. Normally, this would make an audiences heads spin, but she has such a grasp of the material and such a clear way of presenting it that she had everyones rapt attention.

Its this same completeness and clarity that youll find in this book, in chapters ranging from the basics in the details youll need to write actual applications for your actual business needs. If there is more material to lead you through the basics of the Entity Framework and to be a continuing reference, I dont know what it is.

During her presentation, Julie fielded questions on all manner of EF details and related topics, but the one that made me cringe under the weight of history is the one I always get, too: Why should we use EF when Microsoft has already given us so many other data access technologies? Julies answer came without hesitation: Because its the best!

Now, as a Microsoft employee sensitive to the needs of a wide-range of customers across a wide-range of needs, I have to say that officially you should use the technology that best fits your specific business problem. I can also say that the Entity Framework is the .NET technology against which were placing all of our future bets and making all of our biggest investments, which means that its the technology that we hope meets most of your needs now and will meet more of your needs in the future.

But, I have to say, I do like Julies answer a great deal.