Flexible Relations - Operational Support of Variant Relational Struetures

Kalus, Christian and Dadam, Peter (1995) Flexible Relations - Operational Support of Variant Relational Struetures. In: Proc. Int. Conf. on Very Large Databases, (VLDB '95), Zürich, Switzerland.

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The relational model is accepted for its simplicity and eIegance. At the other side the simplicity causes the problem, that most semantic type constructs are not representable as a simple relation. Variant and heterogeneous structures belong to those constructs not adequatly supported by the simple relational model. In this paper we give an overview of the model of flexible relations that allows to model and process arbitrary heterogeneous structures, while preserving the relational philosophy of operating with a single constructor. As flexible relations support both the modeling and the operational aspect of variant structures seamlessly, our model truly helps to further bridge the gap between semantic and operational data models. We discuss the structural part of the moQ.el and introduce an algebra for flexible relations. Further we examine a subdass of flexible relations, that can be processed as efficiently as the simple relational model, and show that this subdass possesses desirable structural normal form properties. In addition, we point out that our approach exceeds the objectoriented paradigm in modeling power, typing precision, and query optimization potential.

Item Type: Conference or Workshop Item (Paper)
Subjects: DBIS Research > Publications
Divisions: Faculty of Engineering, Electronics and Computer Science > Institute of Databases and Informations Systems > DBIS Research and Teaching > DBIS Research > Publications
Depositing User: Eva Mader
Date Deposited: 08 May 2008 09:54
Last Modified: 14 Oct 2011 10:25
URI: http://dbis.eprints.uni-ulm.de/id/eprint/319

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