DB2 University is a site that offers free online courses in basic SQL as well as DB2, Data Studio, and other technologies. The courses are self-paced and guide students through series of exercises. Course completion is recognized with a certificate.
At the time of writing, DB2 University boasts of nearly 6000 students worldwide who've taken a quick course or two and bolstered their database skills.
The Big Data University sister site is running an interesting promotion for its Hadoop Fundamentals I course. The best three students who complete the free Hadoop course and an additional exercise for October 3rd will get to go on an expenses-paid five day trip to Las Vegas and attend the Information on Demand 2011 conference.
Hadoop is an open source programming framework for processing large quantities of data in computer clusters. It's part of IBM's InfoSphere BigInsights offering.
DB2 Community Team