What is a good internet tutorial on learning AJAX and database management

Here are some good learning pages and tutorials for AJAX and databases: Creating a MySQL connection with PHP/AJAX: http://www.johnwiseman.ca/blogging/?p=61... Building an AJAX-Based Chat: Interacting With a Database: http://www.devarticles.com/c/a/xml/build... Very Dynamic Web Interfaces: http://www.xml.com/pub/a/2005/02/09/xml-... XML in the Browser: Submitting forms using AJAX: http://tinyurl.com/9jx59/xml-in-the-brow... How to Use AJAX: http://www.informit.com/articles/article... A Simpler Ajax Path: http://www.onlamp.com/pub/a/onlamp/2005/...