I have worked with database applications for most of my career, and have been a SQL Server DBA for the last thirteen years. I started with the computer industry in 1981, the year the first IBM Personal Computer, running DOS 1.0, was released. In fact, I owned one of the first models off the production line.
My first exposure to a database application was in 1982. It was called TIM (Total Information Management) and was written by some guys in Lenexa, KS, in ROM BASIC, the version of BASIC that was built into the first IBM PCs. TIM was slow, hard to use, and very buggy, but it whetted my taste for databases. In 1984, the same developers built a product suite called Smartware, which included a more-sophisticated database application. This is when I first learned how to design databases and develop database applications.
It wasn't until 1996 that I began to get serious about being a full-time DBA. At the time, I was working as a Microsoft Certified Trainer, teaching virtually every certification class Microsoft offered at the time, including networking, development, Exchange, and SQL Server. I soon realized that I could not keep up with that much technology and that I needed to specialize. I considered many options, finally narrowing it down to becoming a DBA, specializing in Microsoft SQL Server. One of the deciding factors was my positive past experience working with databases.
I quit my job as a trainer and set out to become a DBA. While I had some experience with databases, and a good technical knowledge of SQL Server (from teaching it), I had never worked with databases on a full-time basis. Lacking this "real" experience, I knew I was taking a risk, but you have to start somewhere.