How to Build Your Own Moving Objects Database System

Representing descriptions of movements in databases and querying them is a basic capability required in mobile data management. In this article we present a prototype of a moving objects database system and an environment for building such prototypes called Secondo. The Secondo environment is freely available on the Web. The prototype of a moving objects DBMS is based on the concept of spatio-temporal data types, providing abstractions such as moving point and moving region. These can represent time dependent positions or objects with extent, respectively, such as vehicles or forest fires. Moving point and moving region are offered as data types with suitable operations. We explain the basic idea, the distinction between abstract and discrete model, and the design principles for an abstract model with carefully designed types and operations. The discrete model defines finite representations for all data types and can serve as a blueprint for implementation.