Optimization of Multiple Continuous Queries over RFID Streaming Data

RFID technology enables a new era of business optimization. With the development of RFID technology, more and more RFID applications have been developed. In RFID system, RFID middleware collects, filters, and integrates large volume of streaming data gathered continuously by heterogeneous readers to process queries from applications. These queries are called continuous queries as they are executed continuously to extract useful information from data streams. EPCglobal proposed an Event Cycle Specification (ECSpec) model, which is a de facto standard query interface for RFID middleware. When the middleware system processes many continuous queries, query optimization is quite important for their execution and enhancing the performance of the system. In this paper, we propose a multiple continuous query optimization method for RFID data streams, which is based on query (ECSpec) execution conditions and filter conditions analysis. Keywords-RFID middleware; Continuous queries; Query optimization.