Expert T-SQL Window Functions in SQL Server

Book Preface

SQL Server is a powerful database platform with a versatile query language called T-SQL. The most exciting T-SQL enhancement over the past decade is, without a doubt, window functions. Window functions enable you to solve query problems in new, easier ways, and with better performance most of the time.

After the release of SQL Server 2000, SQL Server enthusiasts waited five long years for the next version of SQL Server to arrive. Microsoft delivered an entirely new product with SQL Server 2005. This version brought SQL Server Management Studio, SQL Server Integration Services, snapshot isolation, and database mirroring. Microsoft also enhanced T-SQL with many great features, such as Common Table Expressions (CTEs).

The most exciting T-SQL enhancement of all with 2005 was the introduction of window functions. That was just the beginning. Window functions are part of the ANSI Standard SQL specification, and more functionality according to the standard was released with version 2012 of SQL Server. Even now, the functionality falls short of the entire specification, so there is more to look forward to in the future.

Contents:

About the Authors …………………………………………………………………..xi
About the Technical Reviewer ………………………………………………..xiii
Acknowledgments …………………………………………………………………xv
Author’s Note ………………………………………………………………………xvii
â– â– Chapter 1: Looking Through the Window …………………………………1
â– â– Chapter 2: Discovering Ranking Functions …………………………….17
â– â– Chapter 3: Summarizing with Window Aggregates ………………….33
â– â– Chapter 4: Tuning for Better Performance ………………………………47
â– â– Chapter 5: Calculating Running and Moving Aggregates ………….61
â– â– Chapter 6: Adding Frames to the Window ………………………………71
â– â– Chapter 7: Taking a Peek at Another Row ………………………………83
â– â– Chapter 8: Understanding Statistical Functions ………………………97
â– â– Chapter 9: Time Range Calculations and Trends ……………………107
Index ………………………………………………………………………………….129