Wireless sensor networks (WSN) are in use in a wide range of areas. Historically, they have been mostly used for passive surveillance of physical phenomena and data logging activities where measurements are transferred and stored outside the actual network. In recent years, with the emerge of Internet of Things (IoT) technologies and Vehicle2X communication scenarios novel challenges for wireless sensor network platforms - regarding hardware and software - arose. Queriable wireless sensor networks enable users to specify measurement tasks in a declarative way and thus allow also non-technicians to define network applications. Most current WSN applications feature active parts with which nodes can directly influence their environment, hence they are called wireless sensor actuator networks (WSAN). However, these actuator actions are often defined from outside the network in response to aggregated measurements or detected events, i.e. in a global fashion. In this paper, we propose a way to extend existing queriable wireless sensor network implementations in order to allow them to respond to events and to control actuators in an energy-efficient, timely and local manner which in turn improves the adaptivity and energy-efficiency of the network and its application. Additionally, we will show that this event system is viable to support distinct types of the sub query problem in WSN.