Distributed Mobile Database Query Processing Techniques

In recent years, mobile computing and mobile database have developed rapidly and been applied in many fields successfully. There is a new organization form for mobile database after the appearance of MANET and broad study on data broadcasting cache strategy and data replication for this new database system have been conducted well, however, the study on query process and query optimization have a long way to go.This paper is based on the characteristics of MANET mobile database system, which includes multi-hop routing, limited energy nodes movement and disconnection frequency etc. The query plan presentation model based on multi-label tree and the cost model based on energy transmission are both raised. Moreover, this paper designs two stage query optimization algorithm based on energy and adaptive recursive join algorithm and prototype MDSMS is implemented.The result of experiment shows that two stage query optimization algorithm based on energy and adaptive recursive join algorithm could save query energy consumption effectively and speed up enquiry response time.