Sensor Network Query Processing Technology Research

In pace with rapid development and increasingly maturation in communication technique, embedded technique and sensor equipments, micro-sensor equipments with sensoring, computing and communicating abilities has appeared all over the world. We are paying more attention on sensor network constructed by these equipments, but because of the mobility, low bandwidth and disconnection of nodes, there are lots of challenges about sensor networks. The existing query processing technique is not advanced, too many hypotheses and limitations exist in most of mechanism and algorithm and some key functions cannot be supported.This paper mainly studys the technologies of query processing in sensor network,.We explore a kind of SQL-like query language and adopt the relational data model. This article proposes correspondingly query plan and query optimization model to the query with and without join operation. Regarding the query without join operation, this article proposes three kind of query plans, sensor network will choose the different execution plan in view of the query nature and the network resources; Regarding the query with join operation, this article has mainly solved two regions join and the multi-regions join query problems, we present the TRHJ (Two Region Hash Join) algorithm based on half join and hash join technologies and MRJ (Multi-Region Join) algorithm based on Delaunay triangulation. The experiment proves that the TRHJ algorithm used hash and half join technologies has saved the transmission energy greatly and at the same time it has also reduced the computing time of nodes in sensor networks; The MRJ algorithm based on the Delaunay triangulation method with low time complexity, solves the multi-regions join problem, the test result comparison...