If you use Joomla, then you use MySQL.
MySQL is the world's most popular database program and if you build Joomla sites, you'll benefit from an understanding of MySQL.
Today we're giving away 10 copies of the best-selling book, MySQL Explained. This book was published 6 months ago, and has been sitting on top of Amazon's listings ever since.
MySQL Explained is a clear, step-by-step guide that will enable you to understand how your data is being stored and give you the ability to design your own custom applications!