SQL in a Nutshell, 2nd Edition

Why This Book?

The primary source of information for relational databases is the documentation and help files provided by the vendors themselves. While each vendor’s documentation is an indispensable resource that most database programmers and database administrators turn to first, it has a number of limitations:

• It covers only a single, specific vendor’s product. There is no coverage for translation, migration, or integration issues.

• It describes programming methods, usually in a multitude of small, disconnected documents or help files.

• It covers individual commands, often in confusing detail, obscuring the simple and direct uses of commands that are used every day by programmers and administrators.

In other words, the documentation included with the vendor database is an exhaustive explanation of every aspect of their platform. After all, help texts are naturally geared toward delivering the main facts about the product. They’ll tell you a command’s specific syntax (and all its obscure variants) and, in general terms, how to implement it. However, if you move between RDMS’s and you need to be productive very quickly, you will rarely use those obscure command variations and instead utilize the common capabilities in real-life situations.

This book begins where the vendor documentation ends by distilling the experiences of professional database administrators and developers who have used these SQL variants day in and day out to support complex enterprise applications. You’ll get the benefit of their experience in a compact and easily usable format. Whether SQL is new to you or you have been using SQL since its earliest days, there are always new tips and techniques to learn. And, when moving between different implementations, it’s always important to find out about the implementations that can bite you if you’re not careful and informed.