Refactoring has proven its value in a wide range of development projects, helping software professionals improve system designs, maintainability, extensibility, and performance. Now, for the first time, leading agile methodologist Scott Ambler and renowned consultant Pramodkumar Sadalage introduce powerful refactoring techniques specifically designed for database systems. Ambler and Sadalage demonstrate how small changes to table structures, data, stored procedures, and triggers can significantly enhance virtually any database design - without changing semantics. You'll learn how to evolve database schemas in step with source code - and become far more effective in projects relying on iterative, agile methodologies. This comprehensive guide and reference covers every fundamental concept underlying database refactoring, and helps you overcome the practical obstacles to refactoring real-world databases. Start-to-finish examples walk you through refactoring both simple standalone database applications and sophisticated multi-application scenarios. You'll master every task involved in refactoring database schemas, and discover best practices for deploying refactorings in even the most complex production environments. The second half of this book systematically covers five major categories of database refactorings. You'll learn how to use refactoring to enhance database structure, data quality, and referential integrity; and how to refactor both architectures and methods. The book provides an extensive set of examples, built with Oracle and Java, and easily adaptable for other languages, such as, C#, C++, or VB.NET. Using this book's techniques and examples, you can reduce waste, rework, risk, and cost - and build database systems capable of evolving smoothly, far into the future.