Location Management Of Mobile Object And Location Dependent Query Strategy In Mobile Real-time Database

With the rapid development of computer technology, People's demand has changed a lot in the environment of data-processing, the most prominent feature of which is that mobility has been proposed in the environment of data-processing Traditional database technology has been unable to meet the emerging demand for this mobile environment, so the demand for mobile computing technology has emerged. In the impulse of mobile computing technology, Database technology is gradually developing towards Mobile Database technology. At present, the research of mobile real-time database has become a hotspot, which gradually makes the demand for accessing any data at any place and any time become a reality.Location Management as a number of applications in the mobile environment is an important and indispensable component, also is the premise of mobility for system. In the Location Management Strategy, use a six-tuple to describe location information of mobile objects in the system, and a two-tier model to store location information. In addition, design an efficient location update strategy based on the balance of factors and a way to Area-Switching, and through a two-tier judgments Model come true transparent Area-Switching of mobile objects, which provides an effective support for the Mobile feature of system .In the Location Dependent Query strategy, system effectively achieve the rapid mapping between Location information and Data Region by a method based on grid combination and two level of index, so that resolve the most critical issue of the Location Dependent Query, at the same time, by analyzing the Location Dependent Query of mobile real-time environment, introduce an initiative Subscribe mechanism in the query strategy to support the local implementation of mobile terminal.