GrHyMM: A Graph-Oriented Hybrid Multidimensional Model

The main methodologies for the data warehouse design are based on two approaches which are opposite and alternative each other. The one, based on the data-driven approach, aims to produce a conceptual schema mainly through a reengineering process of the data sources, while minimizing the involvement of end users. The other is based on the requirement-driven approach and aims to produce a conceptual schema only on the basis of requirements expressed by end users. As each of these approaches has valuable advantages, it is emerged the necessity to adopt a hybrid methodology which combines the best features of the two approaches. We introduce a conceptual model that is based on a graph-oriented representation of the data sources. The core of the proposed hybrid methodology is constituted by an automatic process of reengineering of data sources that produces the conceptual schema using a set of requirement-derived constraints.