Definate a great series of articles to read if you are at all interested in creating solid database driven web applications.
ONLamp.com — MySQL Crash Course
MySQL Crash Course
by John Coggeshall
Welcome to another issue of PHP Foundations. Last time, I wrapped up a discussion of an ongoing topic of security and good practices I’ve dubbed “PHP Paranoia.” Today I will be changing gears yet again and discuss a cornerstone of any sizable web application â€” a database back end. Specifically, I will be spending the next few columns discussing the MySQL database, starting with today’s article, which will serve as a crash course in SQL. For those of you who are familiar with relational databases such as MySQL, today’s column may not be necessary for you; it contains no PHP code. Instead, I will introduce the concepts of relational databases and the language used to manipulate the data within them. Those of who haven’t been exposed to relational databases, however, read on!