The aim is to construct efficient query processing strategies in a general distributed database environment. The database management systems at different sites may bedifferent; the network can be a local network or a long.haulnetwork or an interconnection of local networks by longdistance lines; the queries submitted by the user can be standard database queries or logic queries, permitting deduction. The system being developed needs to be capable of learning important semantic information from previously processed queries so that future queries can be processed efficiently. In this project, new strategies will be implemented and their performance will be compared to strategies proposed by other researchers. An integration of useful strategies will be carried out. Results in the following areas are expected: new techniques to acquire knowledge for semantic query optimization; new techniques to process logic queries efficiently; and implementation principles for efficient query processing. These results will have a significant influence on the design of advanced query processing systems.
