Authors:
Stefan Berger
and
Michael Schrefl
Affiliation:
University of Linz, Austria
Keyword(s):
Data integration systems, Heterogeneous data sources, Federated data warehouses, Distributed query processing, Software engineering.
Related
Ontology
Subjects/Areas/Topics:
Coupling and Integrating Heterogeneous Data Sources
;
Data Warehouses and OLAP
;
Databases and Information Systems Integration
;
Enterprise Information Systems
Abstract:
Recently, Federated Data Warehouses – collections of autonomous and heterogeneous Data Marts – have become increasingly attractive as they enable the exchange of business information across organization boundaries. The advantage of federated architectures is that users may access the global, mediated schema with OLAP applications, while the Data Marts need not be changed and retain full autonomy. Although the underlying concepts are mature, tool support for Federated DWs has been poor so far. This paper presents the prototype of the “FedDW” Query Tool that supports distributed query processing in federations of ROLAP Data Marts. It acts as middleware component that reformulates user queries according to semantic correspondences between the autonomous Data Marts. We explain FedDW’s architecture, demonstrate a use-case and explain our implementation. We regard our proof-of-concept prototype as a first step towards the development of industrial strength query tools for DW federations.