Indexing Mobile Objects

Abstract

The past few years have shown a significant increase in the volume and diversity of data stored in database management systems. Among these are spatiotemporal data, one of the faster developing categories of data. This phenomenon can be attributed to the flurry of application development concerning continuously evolving spatial objects in several areas: mobile communication systems, military equipment in battlefields, air traffic, truck fleets, and others. In standard database applications, data remain unchanged unless an update is explicitly stated. Applying this mode of operation to constantly moving objects would require frequent updates to be performed; otherwise, the database would be inaccurate and unreliable. In order to capture continuous movement and to avoid unnecessary updates, object positions are stored as time-dependent functions, requiring updates only when a function parameter changes. The moving objects are considered responsible for updating the database about alterations in their movement. In the following article is a short review on basic indexing schemes for accommodating moving objects in database systems so that complex queries about their location in the past, present, and future can be served.