YAM2YAM2: a multidimensional conceptual model extending UML

This paper presents a multidimensional conceptual Object-Oriented model for Data Warehousing and OLAP tools, its structures, integrity constraints and query operations. It has been developed as an extension of UML core metaclasses to facilitate its usage, and try to fill the absence of a standard model. Being a UML extension allows reusing modeling constructs and techniques, and integrating multidimensional modeling in more general modeling processes. Moreover, while existing multidimensional models are restricted to the modeling of isolated stars, this paper investigates the representation of several semantically related star schemas. Summarizability and identification constraints can also be represented in the model, and a closed and complete set of algebraic operations has been defined in terms of functions (so that mathematical properties of functions can be smoothly applied).