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Geoinformatica (2011) 15:497540 DOI 10.1007/s10707-010-0114-3
Spatiotemporal pattern queries
Mahmoud Attia Sakr Ralf Hartmut Gting
Received: 16 November 2009 / Revised: 30 June 2010 / Accepted: 22 July 2010 / Published online: 12 August 2010 Springer Science+Business Media, LLC 2010
Abstract This paper presents a novel approach to express and evaluate the complex class of queries in moving object databases called spatiotemporal pattern queries (STP queries). That is, one can specify temporal order constraints on the fulfillment of several predicates. This is in contrast to a standard spatiotemporal query that is composed of a single predicate. We propose a language design for spatiotemporal pattern queries in the context of spatiotemporal DBMSs. The design builds on the well established concept of lifted predicates. Hence, unlike previous approaches, patterns are neither restricted to specific sets of predicates, nor to specific moving object types. The proposed language can express arbitrarily complex patterns that involve various types of spatiotemporal operations such as range, metric, topological, set operations, aggregations, distance, direction, and boolean operations. This work covers the language integration in SQL, the evaluation of the queries, and the integration with the query optimizer. We also propose a simple language for defining the temporal constraints. The approach allows for queries that were never available. We provide a complete implementation in C++ and Prolog in the context of
the Secondo platform. The implementation is made publicly available online as a Secondo Plugin, which also includes automatic scripts for repeating the experiments in this paper.
Keywords Moving objects databases Trajectory Lifted predicate
Spatiotemporal patterns Secondo
M. A. Sakr (B) R. H. Gting
Database Systems for New Applications, FernUniversitt in Hagen, 58084 Hagen, Germanye-mail: [email protected]
R. H. Gtinge-mail: [email protected]
M. A. SakrFaculty of Computer and Information Sciences, University of Ain Shams, Cairo, Egypt
498 Geoinformatica (2011) 15:497540
1 Introduction
The area of moving objects databases has been active since the early 2000s, and is recently receiving a lot of interest because of the advances in the positioning and sensor technologies that generates large amounts of moving objects data. These databases deal with the geometries that change over time, also called spatiotemporal data. There are two classes of models for such data. The first deals with the current movement and the predicted near future (e.g....