Difficult to say really.
Personally, I'd choose which ever topic excited me the most. If, for example, you decide to do your research on Data Mining and you found the subject boring, then you'll likely lose your passion for the research.
You also mention the database security as DBA. A DBA does much more than just manage security on the database servers. There are a number of different areas a DBA will cover - some they will specialise in and some they will have sufficient knowledge to get them through.
Thanks
Clive
http://www.sqlsvrdba.com- Marked As Answer byElsamelghi Tuesday, November 03, 2009 12:40 PM
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