In this paper, we provide further extensions of Hand-OLAP, a Java-based distributed system for enabling OLAP in mobile environments via intelligent data cube compression approaches. These extensions aim at integrating innovative semantics representation and management models within compressed OLAP views, in order to improve the data cube compression process itself, and to support an improved su...

On-line analysis of clinical study data has not benefited from recent advances in OLAP technologies. We examine the analysis requirements posed by the biotech domain that are not met by traditional OLAP. To accommodate these new requirements, we propose the concept of Scientific OLAP which applies more broadly to data analysis in controlled scientific experiments. We describe our experience imp...

Multidimensional data warehouses and OLAP systems do not provide adequate means for dealing with changes in dimension data, changes appearing frequently in dynamic application areas as current business systems. As data warehouses and OLAP tools serve as decision support systems they have to reflect such changes. Temporal data warehouses propose sophisticated modelling tools for covering any cha...

Data warehouses and Online Analysis Processing (OLAP) have acknowledged and efficient solutions for helping in the decisionmaking process. Through OLAP operators, online analysis enables the decision-maker to navigate and view data represented in a multi-dimensional manner. But when the data or objects to be analyzed are complex, it is necessary to redefine and enhance the abilities of the OLAP...

The use of OLAP sessions, conducted by professional analysts, seems to be the best way to assess the relevance of OLAP solutions based on former queries (in particular with user-centric approaches, like recommendation or personalization of queries). However, for scholar research teams, obtaining such logs is often difficult. Moreover, the complexity of the queries produced in these logs can lea...

In this paper, we present an OLAP framework for trajectories of moving objects. We introduce a new operator GROUP TRAJECTORIES for group-by operations on trajectories and present three implementation alternatives for computing groups of trajectories for group-by aggregation: group by overlap, group by intersection, and group by overlap and intersection. We also present an interactive OLAP envir...

We propose a framework for efficient OLAP on networks with a focus on the most interesting kind, the topological OLAP (called “TOLAP”), which incurs topological changes in the underlying networks. Topological OLAP operations generate new networks from the original ones by rolling up a subset of nodes chosen by certain constraint criteria. The key challenge is to efficiently compute measures for...

In today’s OLAP systems, integrating fast changing data physically into a cube is complex and time-consuming. Our solution, the “OLAP-XML Federation System,” makes it possible to reference the fast changing data in XML format in OLAP queries without physical integration. In this paper, we introduce the novel query optimization techniques specialized for the federation system including a query o...

Data warehouses and Online Analysis Processing (OLAP) have acknowledged and efficient solutions for helping in the decisionmaking process. Through OLAP operators, online analysis enables the decision-maker to navigate and view data represented in a multi-dimensional manner. But when the data or objects to be analyzed are complex, it is necessary to redefine and enhance the abilities of the OLAP...

OLAP queries involve a lot of aggregations on a large amount of data in data warehouses. To process expensive OLAP queries efficiently, we propose a new method for rewriting a given OLAP query using various kinds of materialized aggregate views which already exist in data warehouses. We first define the normal forms of OLAP queries and materialized views based on the lattice of dimension hierar...