Synopsis:
At this point, when considering purchasing this book, I'd say get a real reference if you want to learn PHP, or if you need a big function reference off-line, then install the help that comes with PHP or just use php.net on-line. This book might be marginally okay for bathroom reading, but otherwise, it really needs to be updated. The reference only covers through PHP 4 which is now unsupported. The way things are done in PHP 5 have changed enough that it's time to deprecate this resource.
Details:
I've owned this pocket reference since it was published in '02 and put it away when I switched to Perl as my primary language in '04 till this year. Now that I'm back to PHP again, I'm reminded of how annoying it is to use this book. The tips at the front of the book are good, but the function reference is difficult to use at best. I'm terribly surprised that O'Reilly hasn't worked with Mr. Lerdorf for a new version. I own lots of O'Reilly materials, many of them pocket references. I don't believe this is up to O'Reilly standards for pocket references. If given a chance to review a new version of this reference, I'd push hard for significant changes, especially to formatting. Other reviewers correctly identified issues with function descriptions. There are times when a pocket reference like this deserves to skip descriptions when the description doesn't add any value to what's already obvious.
Hit(s):
o Contains basic PHP syntax information
Miss(es):
o The latest PHP version covered in this book is no longer supported
o Function listing is grouped in a manner that doesn't make sense to most readers
o Function descriptions are often worthless