Back in December 
of 2007, Andrew E. Bruno wrote an excellent article on how to use the open source program Dia to design databases. He used the resultant design to create a MySQL database but the same principles could be used to create just about any relational database from the design. Dia is available for Linux, *nix, and Windows.
Database Design with Dia
In this post I’m going to give a quick how-to on creating database schemas with a wonderful tool called Dia. I’ve often found having a nice visual representation of a database to be quite helpful but can’t stand keeping it up to date. As soon as you add a new column or change the design around you end up having to sync your visual diagram with your SQL files. It’s tedious having to manage the various SQL for building the database and this can be a larger pain when trying to support different database platforms each with their own SQL syntax. So before you create your next database read on and see how Dia can make your life a bit easier.
Dia is a program for creating diagrams and for this exercise we’ll be creating UML diagrams from within Dia. We’re also going to use a perl script called tedia2sql which will transform our Dia files directly to SQL for our target database. What’s also nice about creating database schemas this way is that you can generate SQL for multiple target databases without the maintenance overhead.
The CakePHP website shows us how:
