I have been doing php/MySQL development for many years now and have started looking at distributing applications. One or the issues that I have come up with the the creation and updating of the database schema. I started developing this class on a project that was creating a WordPress plugin that the client was hoping to resell. I had been working with WP eCommerce and sae how they managed their schema and developed this system that overcomes some of the shortcomming of that system. This class can be used to: 1 - extract a database schema into a php script that defines the schema in an array. 2 - apply the extracted script to recreate the database schema. 3 - Allow the editting of the extracted script to impment changes to the schema. 4 - Allow users of the application to create changes to the schema that are separate to the extracted script. 5 - Support for pre and post processing scripts. 6 - Require a minimum schema version to apply the update.