Paul, we are working on an Online Tutorial that will explain and teach the principles of database schema design. It will be available next year.
Also, we are going to perform a workshop about Schema Design with MySQL Workbench at the upcoming MySQL Users Conference.
http://en.oreilly.com/mysql2009/public/content/home
We will run it every day. So if you are coming to the conference you can take the free workshop run by one of our professional MySQL trainers. The MySQL Workbench team will also be around helping you and answering your questions while using MySQL Workbench.
I know you'd rather need something right now, but we are just in the process of putting the comprehensive tutorial together.
Hope to see you at the MySQL UC!
Mike
Michael Zinner, Team Lead, Developer Tools
MySQL AB, www.mysql.com
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