T-SQL Window Functions - Itzik Ben-Gan - Bog

Use window functions to optimize your T-SQL queries for greater simplicity, elegance, and performance Discover the surprising power of window functions, and learn how to use them far more widely The most advanced coverage of T-SQL window functions — including new techniques invented by author Itzik Ben-Gan, one of the world's top T-SQL experts Covers T-SQL for all recent versions of Microsoft SQL Server (including 2019) and Microsoft Azure SQL Database — including important new window function optimizations Ideal for DBAs, developers, and anyone who uses T-SQL to solve business problems Most T-SQL developers recognize the value of window functions for data analysis calculation. But window functions can do far more than that, and optimizations in recent versions of SQL Server have made them more powerful than ever. In T-SQL Window Functions: For Data Analysis and Beyond, renowned T-SQL expert Itzik Ben-Gan introduces breakthrough techniques for using window functions to handle many common T-SQL querying tasks with unprecedented elegance and power.
Ben-Gan first explains why window functions can often be a far better solution than traditional predicate-based approaches. Next, using extensive code examples, he guides you through each type of window function: Aggregate, Ranking, Distribution and Offset. You'll find detailed coverage of ordered set functions (including SQL Server 2017's STRING_AGG); plus an extensive section on optimization. The book concludes with roughly 100 pages of real T-SQL solutions using window function approaches — including techniques invented by the author and available in no other book.