A Tool for Transforming Conceptual Schemas of Spatio-Temporal Databases with Multiple Representation

摘要

Nowadays, classical conceptual models (such as ER or UML) are used for designing database applications. These classical conceptual models usually come with associated CASE tools assisting the user from the creation of the conceptual schema until the generation of a physical schema for a relational or an object-relational DBMS. However, when developing spatial or temporal databases such classical models are inadequate since they do not consider spatio-temporal concepts. Although spatial and/or temporal extensions have been proposed for these models, such extensions do not cope with the requirements of advanced geographical applications, in particular, they do not cope with multiple representations of the same real-world phenomenon. In the context of the European project MurMur we developed a conceptual model called MADS coping with spatio-temporal information having multiple representations. Typical examples of multiple representation arise with multi-scale or time-varying information. The MADS model is supported by a set of associated tools allowing both the definition of the schema and the queries of the application at a conceptual level. Such conceptual specifications are then automatically translated into the language supported by the target GIS and/or DBMS software (e.g., SQL schema definitions or queries for an Oracle database). In this paper we describe a Translator module that allows to implement conceptual MADS schemas into target platforms. It is composed of a Transformation module that translates conceptual MADS schemas into a more simple schema using only concepts supported by the target software, and a Wrapper module that generates the data structures in the language of the GIS and/or DBMS software.