Learn More
In the last years, lots of work have been devoted to multidimensional modeling, star shape schemas and OLAP operations. However, "drill-across" has not captured as much attention as other operations. This operation allows to change the subject of analysis keeping the same analysis space we were using to analyze another subject. It is assumed that this can(More)
The words On-Line Analytical Processing bring together a set of tools, that use multidimensional modeling in the management o f information to improve the decision making process. Lately, a l o t o f w ork has been devoted to modeling the multidimensional space. The aim of this paper is twofold. On one hand, it compiles and classiies some of that work, with(More)
OLAP tools divide concepts based on whether they are used as analysis dimensions, or are the fact subject of analysis, which gives rise to star shape schemas. Operations are always provided to navigate inside such star schemas. However, the navigation among different stars is usually overlooked. This paper studies different kinds of Object-Oriented(More)
OLAP defines a set of data warehousing query tools characterized by providing a multidimen-sional view of data. Information can be shown at different aggregation levels (often called granular-ities) for each dimension. In this paper, we try to outline the benefits of understanding the relationships between those aggregation levels as Part-Whole(More)
"On-Line Analytical Processing" tools are used to extract information from the "Data Warehouse" in order to help in the decision making process. These tools are based on multidimensional concepts, i.e. facts and dimensions. In this paper we study the meaning of facts, and the dependencies in multidimensional data. This study is used to find relationships(More)
This paper presents a multidimensional conceptual Object-Oriented model, its structures, integrity constraints and query operations. It has been developed as an extension of UML core metaclasses to facilitate its usage, as well as to avoid the introduction of completely new concepts. YAM 2 allows the representation of several semantically related star(More)
In recent years, data warehouses have reached a prominent position in the database field, especially in the database industry. There are many issues in common between data warehouses and other database fields such as federated databases; in our opinion this fact has not been explored in its entirety. In this paper, an integrated database architecture in(More)