From the DevChix website, there's this new post that helps introduce developers (both in PHP and Rails environments) to hos to use the Yahoo! UI connection manager in their applications.

This post is geared towards folks who haven't done the "A" part of "AJAX" before (And I mean the first "A", as in "Asychronous"); are new to Yahoo's implementation of the XMLHttpRequest object (The Yahoo! Connection Manager) and would like added information on how that works; or both.

Sarah starts off slow with an example of making a connection to a backend PHP script as called by a HTML form. The simple example is fleshed out with a database backend (via PEAR::DB) and the Javascript to handle the response and the errors that might arise. Finally, a request can be made and the result eval-ed to give the client a nice, simple Javascript object to work with.