Multi-Level Domain Modeling with M-Objects and M-Relationships

B. Neumayr, K. Grün, M. Schrefl
Neum09a (2009)
Markus Kirchberg, Sebastian Link (eds.): Proceedings of the 6th Asia-Pacific Conference on Conceptual Modeling (APCCM), January 20-23, 2009, Wellington, New Zealand, Australian Computer Society, Inc. (ACS), Conferences in Research an d Practice in Information Technology (CRPIT), Volume 96, Conceptual Modelling 2009, Australian Computer Science Communications, Volume 31, No. 6, pp. 107-116, ISBN 978-1-920682-77-4, ISSN 1445-1336, 2009.
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Using traditional semantic data modeling, multi-level modeling can be achieved by representing objects in different abstraction hierarchies, namely classification, aggregation and generalization. This, however, leads to accidental complexity, complicating maintenance and extension. Several modeling techniques, like deep instantiation, powertypes and materialization, have been proposed to reduce unnecessary complexity in modeling objects at multiple levels. Multi-level objects (m-objects) and multi-level relationships (m-relationships) build on these results and provide a natural, intuitive representation of theconcretizationof objects and relationships along multiple levels of abstraction. By integrating aspects of the different abstraction hierarchies in a single concretization hierarchy, they improve readability and simplify maintenance and extension as compared to previous approaches. The discussion on conceptual modeling is complemented by a brief presentation of M-SQL, a data manipulation and query language for working with m-objects and m-relationships in an object-relational setting.

Keywords:Conceptual Modeling, Multi-Level Modeling, Multiple Abstraction