In other words, it don't make no difference! Get whatever is offered in your area.
Many people who administrate SQL server networks do other stuff as well and aren't that highly paid. However, because Oracle is extremely expensive, there are a lot more people who need SQL Server administrators.
You might also look into open source databases like mySQL. People in the Unix world are using those increasingly since you can do almost everything Oracle does, but for a lot less money.
If you want to deal with mySQL or SQL Server, you probably want to look into programming classes. What's nice about mySQL and Linux is that you can run them on your own computer and get a taste for them before taking an (incredibly overpriced) class. Most Linux distributions (such as Red Hat and SuSE, which you can buy pre-packaged at Fry's or CompUSA) include mySQL and you can get the whole package for $50 or so. It's a lot tougher (more expensive) to get your hands on SQL server or Oracle.
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