Bringing it to a close
If you have made it this far without having just jumped to the end as if this were a whodunnit mystery book you should have what I consider to be the full set of skills required to program complex web systems in PHP. In this book we have covered quite a variety of topics, and your average programmer will be fluent in about 60% - some like to make extensions, others like to make GUIs, and yet more seem to be happy enough having memorised all the possible parameters for the date() function. Having given you all of the above plus a lot more, I hope you will be able to make your own way in the PHP world.
Above and beyond knowing just how to program PHP code, I hope you have learnt more about what it means to be a programmer - how to discuss PHP with your boss and your team mates, how to design and deploy solutions you create, how to take into account cross-platform problems, and also how to find problems in your code and fix them easily.
From a technical point of view, we've gone from the very start to the very end of PHP programming, covering nearly everything along the way. I have tried to structure this book so as to maximise its use as a reference guide, and on occasion this has meant things appearing slightly out of the order I would otherwise have wanted - hopefully this hasn't caused you any problems.
The chapter on databases was hopefully detailed enough for all readers. Yes, I did not cover any detail on PostgreSQL, Oracle, or MS SQL Server, but proportionately these are used a great deal less than MySQL and PEAR::DB with PHP - perhaps this can be rectified in a future version, if enough people write in requesting it.
If you read the chapters on alternative uses for PHP and thought they did not apply to you, please read them again - it is quite important to get to grips with the CLI SAPI as it can be a very helpful debugging and prototyping tool. I use the CLIP SAPI all the time when I just want to check something out, or if I want to get more detailed debugging information than would otherwise be available working through a web browser.
Finally, I hope I have inspired you to go out and learn more about PHP programming for yourself. The various sources I have cited that made up this book are real tomes of knowledge that I hope will grace your bookshelves before long - even the ones that concern software design and project management. It is not like I make any cash by recommending these books - I recommend them because I firmly believe they will increase your learning and make you a better programmer.
So, all that is left for me to do now is to thank you for reading this book - there are dozens of PHP learning books and tutorials out there, and I am flattered you chose mine. If you find errors in the text or code presented here, please do write in and let us know so that we can post fixes online for everyone else. Furthermore, if you have suggestions about how this book can be revised or improved in the future, we would love to hear from you also.
Good luck in your programming!