> And about MySQL:
> It's also commercial. You are not supposed to use it except for a
> single machine for personal use unless you are a non-profit organization
> or unless absolutely everything you do is GPL[1]. Hence, you have to
> license it to deploy applications. In order to have transactions, you
> have to use another commercial product that they bolt into MySQL --
> Sleepycat software's database. Now you have two license systems to
> worry about.
Just a correction - you need to use the InnoDB database engine, which is
free and GPL and bundled with MySQL.
Chris