Efficient Management of Schema Versioning in Multi-Temporal Databases
Zouhaier Brahmia1, Mohamed Mkaouar2, Salem Chakhar3, and Rafik Bouaziz1
1Faculty of Economic Sciences and Management, University of Sfax, Tunisia
2Faculty of Science, Mathematics, Physics and Natural, University of Tunis-El Manar, Tunisia
3 LAMSADE Laboratory, University of Paris Dauphine, France
1Faculty of Economic Sciences and Management, University of Sfax, Tunisia
2Faculty of Science, Mathematics, Physics and Natural, University of Tunis-El Manar, Tunisia
3 LAMSADE Laboratory, University of Paris Dauphine, France
Abstract: To guarantee a complete data history in temporal databases, database management systems have to manage both evolution of schema over time, through their versioning, and evolution of data defined under different schema versions. This paper proposes a new approach for schema versioning in multi-temporal databases. It allows an efficient management of schema versions and their underlying data, through a smooth conversion of the temporal database. When creating a new schema version, the basic idea consists in forbidding (i) any automatic transfer of data defined under previous schema versions to this new version, in order to avoid data loss and ambiguousness in the interpretation of temporal intervals of data, and (ii) any change in the structures of previous schema versions, in order to permit to the legacy applications to remain operational after this schema evolution.
Keywords: Schema evolution, schema versioning, temporal databases, multi-temporal databases, application time, and database conversion.
Received July 31, 2010; accepted October 24, 2010