There are many PHP & MySQL  books out there plus many free tutorial helpful for you. However, I choose the best roadmap for you by going the same road a PHP programmer goes for Zend PHP5 Certificate. You are not required to follow step by step and also on each step, I try to point out some places that you may interested jumping to.

So, what you are going to learn are:

• Basic of PHP
• Function, Array and basic programming classes (String, Date, Math, etc.)
• More details about string and patterns
• Web programming basis (HTML, CSS, Form, Session, JavaScript, etc.)
• Object Oriented Programming (OOP)
• Working with MySQL
• Designing OOP web application
• A Simple MVC framework
• XML & Web Service
• Secure your web application
• File and network resources
• Compare PHP4 and PHP5
• Overview of PHP web development engineering
  • PHP Frameworks (Zend, Symfony, Prado, CakePHP, CodeIgniter)
  • Advanced JavaScript
  • Introduce an online Project Management tool
  • Code generation
  • A coding convention reference

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