Tenacious T-SQL code is the code that is designed to last, and will be safe again by someone else. The purpose of defensive database programming, the purpose of this book, is to help you to generate T-SQL code ductile solid and graceful handling of cases of accidental use, and resistant to change in general to the database environment. developer Too often, we stop work immediately after the code we pass some basic tests to confirm that it produces 'the right result' in the case of a given. We did not stop to consider what other possible ways in which the code can be used in the future, or how our code will respond to general changes to the database environment, such as changes in the database language settings, or change to the nullability of the table columns, and so forth. However, if our code is designed to be used for more than a few months, it is very possible that this change can and will happen, and the inevitable result of defective code or, worse still, the code which quietly began to behave differently, or produce results different. Here's what defensive programming is all about: we learn what can go wrong with our code, and we proactively apply this knowledge for development. This book is filled with practical, realistic examples of the kinds of problems that befall a database program, including: - Change the database object, such as tables, constraints, columns, and stored procedures. In the end, this book teaches you how to think and develop self-defense, and how to proactively identify and eliminate potential vulnerabilities in T-SQL code.