Skip to Main Content
The rapid advancement in computing has enabled the development of low cost wireless sensor networks (WSNs), and making WSNs one of the most important research areas. Based on the characteristics and major purpose of WSNs, it has been proposed to integrate sensor network and database technologies to improve the management of data processed from sensor networks. The distributed database is not a new research issue, but in case of WSN, there exists much extra difficulty because there are numerous constraints in WSNs comparing with traditional distributed database, such as limited energy, mobility and heterogeneity. This paper introduces the basic concept of query processing in WSN and how it is performed, presents the state-of-the-art by examining six current related projects, identifies the research challenges highlighted by major related projects, and looks at how the projects proposed to address those research challenges. It has been found that several limitations of the existing related approaches were emerged in mobile and heterogeneous WSN. This paper has also investigated these limitations and discussed the possible future research directions.