This special issue on “Optimization Issues of Querying and Evolving Sensor and Stream Databases” of Information Systems focuses on optimization issues of querying and evolving sensor and stream databases. Sensor and stream databases occur in a wide family of real-life applications, such as monitoring systems, remote control systems in hazardous environments, epidemic intelligence tracking systems, and so forth. Sensors, which physically produce streams, have became pervasive, mostly due to their low per-unit cost and the ability to integrate many of them together.
