5Agrawal S, et al. DBXplorer: A system for keyword-based search over relational databases [C] //Proc of the 18th Int Conf on Data Engineering. Los Alamitos, CA: IEEE Computer Society, 2002:5-16.
6Bhalotia G, et al. Keyword searching and browsing in databases using banks [C] //Proc of the 18th Int Conf on Data Engineering. Los Alamitos, CA: IEEE Computer Society, 2002:431-440.
7Hristidis V, Papakonstantinou Y. Discover: Keyword search in relational databases [C] //Proc of the 28th Int Conf on Very Large Data Bases. San Fransisco, CA: Morgan Kaufmann, 2002: 670-681.
8Hristidis V, et al. Efficient Jr-style keyword search over relational databases [C] //Proc of the 29th Int Conf on Very Large Data Bases. San Fransisco, CA: Morgan Kaufmann, 2003:850-861.
9Luo Y, et al. Spark: Top-k keyword query in relational databases [C] //Proc of the ACM SIGMOD Int Conf on Management of Data. New York: ACM, 2007:115-126.
10Vu Q H, et al. A graph method for keyword-based selection of the top-k databases [C] //Proc of the ACM SIGMOD Int Conf on Management of Data. New York.. ACM, 2008:915- 926.