DevShed have recently published a couple of articles,
Building An Extensible Form Validator Class which looks at building a PHP-based Form Validator object to validate HTML form input and Error Handling In PHP (part 1) shows you how PHP's error-handling functions can be used in real-world development.

At Webmonkey Jay Greenspan has published an article Transactions in MySQL which explains transactions and MySQL's different transactional table types: BDB, Gemini, and InnoDB.

Have a Happy Easter