I wonder how you even know you want to be a DBA if you don't know anything about it? I think most of us are accidental DBAs in the sense that we started doing something else, and the discovered we had an interest and aptitude for database work. I learned database design using MS Access and writing T-SQL queries as a VB programmer. Both gave me an interest in database work and by then I'd learned some essentials of the job. There was still a lot of learn, but I was more than well on my way.

I'd be interested to hear from anyone who "just knew" they wanted to be DBAs. Like one of the previous posters, I'd have trouble hiring someone directly into any of the positions. There are too many designers, both in database design and business intelligence, who lack the ability to see how everything interrelates. Someone coming in new would have to prove to me that somehow they had an intuitive grasp of table design. I didn't have that at first, but as something other than a DBA someone gave me a feel for how it was done.