Dmitri Korotkevitch - Expert SQL Server Transactions and Locking: Concurrency Internals for SQL Server Practitioners

Any source code or other supplementary material referenced by the author in this book is available to readers on GitHub via the books product page, located at www.apress.com/9781484239568 . For more detailed information, please visit http://www.apress.com/source-code .

Some time ago, one of my colleagues asked me, What do you like about SQL Server the most? I had heard this question many times before, and so I provided my usual answer: SQL Server Internals. I like to understand how the product works and solve complex problems with this knowledge.

His next question was not so simple though: How did you fall in love with SQL Server Internals? After some time thinking, I answered, Well, I guess it started when I had to work on the locking issues. I had to learn SQL Server Internals to troubleshoot complex deadlocks and blocking conditions. And I enjoyed the sense of satisfaction those challenges gave me.

This is, in fact, the truth. The Concurrency Model has always been an essential part of my SQL Server journey, and I have always been fascinated by it. Concurrency is, perhaps, one of the most confusing and least understood parts of SQL Server, but, at the same time, it is also quite logical. The internal implementation is vaguely documented; however, as soon as you grasp the core concepts, everything starts to fit together nicely.

It is also fair to say that concurrency topics have always been my favorites. My first few SQL Saturday presentations and first few blog posts were about locking and blocking. I even started to write my first book, the first edition of Pro SQL Server Internals , from Chapter the first chapter in the Locking, Blocking, and Concurrency partbefore going back to write the beginning.

Those few chapters, by the way, were the first and worst chapters I have ever written. I am very glad that I had an opportunity to revisit them in the second edition of Internals book. Nevertheless, I was unable to cover the subject as deeply as I wanted to due to deadlines and space constraints (I am sure that Apress regularly ran out of paper printing the 900-page manuscript in its current form). Thus, I am very glad that I can present you with a separate book on SQL Server locking, blocking, and concurrency now.

If you have read Pro SQL Server Internals before, you will notice some familiar content. Nevertheless, I did my best to expand the coverage of the old topics and added quite a few new ones. I also made many changes in the demo scripts and added the new Blocking Monitoring Framework code, which dramatically simplifies troubleshooting concurrency issues in the system.

This book covers all modern versions of SQL Server, starting with SQL Server 2005, along with Microsoft Azure SQL Databases. There may be a few very minor version-specific differences; however, conceptually the SQL Server Concurrency Model has not changed much over the years.

Nor do I expect it to dramatically change in the near future, so this book should be applicable to at least several future versions of SQL Server.

Finally, I would like to thank you again for choosing this book and for your trust in me. I hope that you will enjoy reading it as much as I enjoyed writing it!