SNQL: a query language for sensor network databases

Database management in the wireless sensor network requires features that are different from the traditional database management. Data are collected from a massively large number of battery-operated sensor nodes in a wireless network. A large amount of dynamically changing data should be temporally queried and collected from the sensor nodes of multiple layers. In this paper, we focus on devising a new query language, SNQL that is efficient in dynamic data collection and energy-saving for massively large sensor networks. To minimize the energy consumption SNQL reduces unnecessary query executions for nodes by adaptive query operations to dynamic environments. SNQL also introduces a querying mechanism of controlling the quality of collected data in association with node selection strategy to minimize the energy consumption for the entire sensor network. We show how the language constructs in SNQL achieve the intended energy efficiency and further show the performance evaluation result.