supported by National Natural Science Foundation of China(No.71090403);Education Ministry of Education of P.R.C(No.x2rj B7110020);Bureau of Science and Information Technology of Guangzhou(No.2011J4100061);Bureau of Science and Information Technology of Zhaoqing(No.2013C001)
The accuracy of predicates selectivity estimation is one of the important factors affecting query optimization performance. State-of-art selectivity estimation algorithms for string predicates based on Pruned countsuf...