Database

So I got this program that has to keep a database of stuff that can change quite a few times.

Except I've never used databases of any kind.

I don't go to school for this (I try to learn all of this myself).

So far I found some stuff
mysql
xml

are there any other databases that I should consider?

>>3
I'd like to know if you're trolling or if you seriously think you're helping. I ask not because >>1 deserves any real help, but because I can no longer tell.