Intended for programmers interested in experimenting with complex user interface elements, this tutorial explores using PHP to generate JavaScript based on data in a database. This tutorial explains a class called chainedSelectors. This class helps you create a SELECT form field that automatically updates the value of another SELECT using JavaScript. PHP is used to retrieve the values for the selectors from a MySQL database. This data is then used to create a JavaScript function that's triggered when the value of the first selector is changed.