This book is in fact an absolute beginner's guide to PHP/MySQL!
This does NOT mean that my grandma would be able to learn how to make dynamic web sites by reading this book, despite the fact that she's never touched a computer in her life.
The scope of this book does not encompass a beginner's guide on how to use a computer nor the basics of web development (such as HTML and CSS) - those things are EXPECTED of those who want to learn PHP.
Without understanding HTML, the very basis of any web document, there is not much point in attempting to learn a web scripting language, such as PHP, which amongst other things deals with dynamically creating HTML by processing various user and browser inputs.
The negative reviews are quite annoying, because the people are voting not on the quality of the material, but on it's subjective incomprehensibility, caused by their own lack of preparation for the consumption of the knowledge contained in this book. It's like you're disappointed that you weren't able to fly an F-15 fighter jet, when you've never operated an aircraft in your life!
Try performing a modicum of research on various web technologies and how they interrelate before buying the first book you see.
As the old adage says: "Learn to walk before you run".
For those who have had some experience in static website creation, this is an excellent book, full of useful examples.
If the code give you errors - check the version of PHP you have installed (type: "php --version" into your server's shell (without the quotations)).
I tried most of the examples (used this book in a class) and they ran just fine under PHP 5.2
And if you encounter some material that's challenging, well that's just a little side-effect of trying to learn something new. It's not always easy, nor should it be.
Contact the author or ask your instructor for clarification (if you're using this at school) and they will surely abide.