I'm going to develop some client-Server software which makes it easy to coordinate projects with project members all over the world (GPL of course). This requires a database on the server side and I don't know very much about databases. Which database should I choose? It has to be free to use, because I'm a student and can't afford to pay for a db, especially not when I'm writing freeware. Is there any grahical interface I could use to design the tables and relations? I already have some stuff I need in an Access database, is it possible to export an Access database to any Linux database?