Spatiotemporal Access Methods [chapter]

Yannis Manolopoulos, Yannis Theodoridis, Vassilis J. Tsotras
2000 Advanced Database Indexing  
The rapid increase in spatio-temporal applications calls for new auxiliary indexing structures. A typical spatio-temporal application is one that tracks the behavior of moving objects through location-aware devices (e.g., GPS). Through the last decade, many spatio-temporal access methods are developed. Spatio-temporal access methods focus on two orthogonal directions: (1) Indexing the past, (2) Indexing the current and predicted future positions. In this short survey, we classify
more » ... access methods for each direction based on their underlying structure with a brief discussion of future research directions. Introduction Spatio-temporal databases deal with objects that change their location and/or shape over time. A typical example of spatio-temporal databases is moving objects in the £ -dimensional space. Moving objects learn about their own location via location detection devices, e.g., GPS devices. Then, the objects report their locations to the server using the underlying communication network, e.g., via wireless networks. The server stores the updates from the moving objects and keeps a history of the spatio-temporal coordinates of each moving object. In addition, the server stores additional information to help predict the future positions of moving objects. Typical queries that are supported by such a server include time slice queries e.g., "Find all objects that cross a certain area at time t" and window queries "Find all objects that cross a certain area in the time interval ¤¥ § ¦ © ¥ " . Time slice queries and window queries may ask about the past, current, or future times. Some queries are concerned only with the past, e.g., trajectory queries "What is the maximum speed of a certain object in the last hour?" Other queries are concerned only with the future, e.g., moving window queries "Find the objects that intersect a moving area in a certain time interval". Numerous research have been done in developing spatio-temporal access methods as an auxiliary structure to support spatio-temporal queries. Figure 1 gives the evolution of spatio-temporal access methods with the underlying spatial and temporal structures. Lines in the Figure indicate the relation between a new proposed spatio-temporal index structure and the original structure that is based upon. The rest of this paper is organized as follow: Section 2 surveys spatio-temporal indexing methods that index the past (i.e., index historical spatio-temporal data). In Section 3, we survey spatio-temporal indexing methods that keep track of the current status of spatio-temporal data. Section 4 surveys the spatio-temporal indexing methods that help answer queries related to the future. In Section 5, we give an overview of available indexing toolkits that can help in implementing spatio-temporal access methods. Finally, Section 6 concludes the paper.
doi:10.1007/978-1-4419-8590-3_7 fatcat:2ubplcflmngf5eiwqdthnlzbzm