Database Systems for Advanced Applications 17th International Conference, DASFAA 2012, Busan, South Korea, April 15-19, 2012, Proceedings, Part I - Lee, Sang-goo; Peng, Zhiyong; Zhou, Xiaofang; Moon, Yang-Sae; Unland, Rainer; Yoo, Jaesoo (Springer Berlin Heidelberg, 2012)