would be a great textbook

If you're an experienced programmer looking for a more streamlined reference manual, I recommend O'Reilly's "Programming PHP" instead.

A good grounding in PHP/mySQL

     I've been entrenched with JSP heavily for the last couple of years, so I haven't familiarised myself with PHP yet. I needed a book that would show me a larger picture than I got in a web developer's job, and showed me how to put it together with more modern techniques.
This book is a perfect example of why I choose O'Reilly whenever in doubt. Chapter 1 is an overview of how web applications are put together. Chapter 2 goes through all the basic PHP syntax (stuff that would take other books several fluffy dry chapters to process). Chapter 3 gets you through all the mySQL and sql basics so you feel comfortable with that, too.
There's no 4 page tutotial entitled: "Using a text editor: Wordpad" There's also no kitch "Employee Database" example cop-out. Instead, Hugh and Dave give a realistic and usable storefront application. This book alone is probably enough for the independent web developer to get a functional site up for her/himself or a client.

A solid and accessible resource for web programmers

     Web Database Applications by Hugh E. Williams (Senior Lecturer, School of Computer Science & IT, RMIT University, Melbourne, Australia) and David Lane (Software Engineer and IT Manager, Multimedia Database Systems Group, RMIT University, Melbourne, Australia) is a solid and accessible resource for web programmers who seek to create powerful, practical, and useful web database applications. Individual chapters address a brief overview of PHP and MySQL, shopping carts, security features, effective querying, and much more. Sample code, black-and-white screenshots, and straightforward instructional text make Web Database Applications a first-class reference and a highly recommended instructional guide.