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Schema Versioning in Data Warehouses: Enabling Cross-Version Querying via Schema Augmentation?

Authors: 
Golfarelli, M; Lechtenborger, J; Rizzi, S; Vossen, G
Year: 
2006
Venue: 
Data and Knowledge Engineering (DKE), 2006

As several mature implementations of data warehousing systems are fully operational, a crucial role in preserving their up-to-dateness is played by the ability to manage the changes that the data warehouse (DW) schema undergoes over time in response to evolving business requirements. In this paper we propose an approach to schema versioning in DWs, where the designer may decide to undertake some actions on old data aimed at increasing the flexibility in formulating cross-version queries, i.e., queries spanning multiple schema versions.

A semantic approach for schema evolution and versioning in object-oriented databases

Authors: 
Franconi, E; Grandi, F; Mandreoli, F
Year: 
2000
Venue: 
Proc. DOOD 2000

In this paper a semantic approach for the specification and the management
of databases with evolving schemata is introduced. It is shown how a general
object-oriented model for schema versioning and evolution can be formalized; how
the semantics of schema change operations can be defined; how interesting reasoning
tasks can be supported, based on an encoding in description logics.

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