Efficiently supporting advanced OLAP visualization of multidimensional data cubes is a novel and challenging research topic, which results to be of interest for a large family of data warehouse applications relying on the management of spatio-temporal (e.g., mobile) data, scientific and statistical data, sensor network data, biological data, etc. On the other hand, the issue of visualizing mult...

Formal concept analysis (FCA) with measures can be seen as a framework for Business Intelligence technologies. In this paper we introduce new ideas about an OLAP cube. We take a focus on a highdimensional OLAP cube reduction and on a hierarchy of attributes in an OLAP cube.

Spatial OLAP (SOLAP) systems do not completely integrate visualization, interaction and analysis functionalities of Geographic Information Systems. In this paper, we propose a flexible Web SOLAP tool, GoOlap, which combines OLAP and Geovisualization functionalities through the integration of the geobrowser Google Earth and the OLAP tool Mondrian/JPivot. Google Earth enriches spatio-multidimensi...

This paper presents an OLAP reporting tool and an approach for determining and processing user OLAP preferences, which are useful for generating recommendations on potentially interesting reports. We discuss the metadata layers of the reporting tool including our proposed OLAP preferences metamodel, which supports various scenarios of formulating preferences of two different types: schema-speci...

Résumé. Les entrepôts de données et l’analyse en ligne OLAP (On-line Analysis Processing) présentent des solutions reconnues et efficaces pour le processus d’aide à la décision. Notamment l’analyse en ligne, grâce aux opérateurs OLAP, permet de naviguer et de visualiser des données représentées dans un cube multidimensionnel. Mais lorsque les données ou les objets à analyser sont complexes, il ...

In this paper, we propose a grid-based On-Line Analytical Processing (OLAP) application which distributes query computation across an enterprise grid. Our application follows a two-tiered process for answering queries based on sharing Cached OLAP data between the users at the local grid site and using grid scheduling approaches to execute the remaining parts of a query amongst a distributed set...

Typical OLAP queries take a long time to be processed so speeding up the execution of each single query is imperative to decision making. ParGRES is an open-source database cluster middleware for high performance OLAP query processing. By exploiting intra-query parallelism on PC clusters, ParGRES has shown excellent performance using the TPC-H benchmark. In this paper, we evaluate ParGRES on a ...

This article deals with OLAP systems based on multidimensional model. The conceptual model we provide, represents data through a constellation (multi-facts) composed of several multi-hierarchy dimensions. In this model, data are displayed through multidimensional tables. We define a query algebra handling these tables. This user oriented algebra is composed of a closure core of OLAP operators a...