K-MEANS BASED APPROACH FOR OLAP DIMENSION UPDATES

Fadila Bentayeb

2008

Abstract

Actual data warehouses models usually consider OLAP dimensions as static entities. However, in practice, structural changes of dimensions schema are often necessary to adapt the multidimensional database to changing requirements. This paper presents a new structural update operator for OLAP dimensions, named Rollup-WithKmeans based on k-means clustering method. This operator allows to create a new level to which, a pre-existent level in an OLAP dimension hierarchy rolls up. To define the domain of the new level and the aggregation function from an existing level to the new level, our operator classifies all instances of an existing level into k clusters with the k-means clustering algorithm. To choose features for k-means clustering, we pro- pose two solutions. The first solution uses descriptors of the pre-existent level in its dimension table while the second one proposes to describe the new level by measures attributes in the fact table. Moreover, we carried out some experimentations within Oracle 10 g DBMS which validated the relevance of our approach.

References

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Paper Citation


in Harvard Style

Bentayeb F. (2008). K-MEANS BASED APPROACH FOR OLAP DIMENSION UPDATES . In Proceedings of the Tenth International Conference on Enterprise Information Systems - Volume 1: ICEIS, ISBN 978-989-8111-36-4, pages 531-534. DOI: 10.5220/0001717905310534


in Bibtex Style

@conference{iceis08,
author={Fadila Bentayeb},
title={K-MEANS BASED APPROACH FOR OLAP DIMENSION UPDATES},
booktitle={Proceedings of the Tenth International Conference on Enterprise Information Systems - Volume 1: ICEIS,},
year={2008},
pages={531-534},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0001717905310534},
isbn={978-989-8111-36-4},
}


in EndNote Style

TY - CONF
JO - Proceedings of the Tenth International Conference on Enterprise Information Systems - Volume 1: ICEIS,
TI - K-MEANS BASED APPROACH FOR OLAP DIMENSION UPDATES
SN - 978-989-8111-36-4
AU - Bentayeb F.
PY - 2008
SP - 531
EP - 534
DO - 10.5220/0001717905310534