Modelling data warehouse structures

Two main problems arise in modelling of data warehouse structures. The first one consists in finding an adequate representation of dimensions in order to facilitate and to control the analysis operations. Second one relates to the modelling of various types of architectures. Research works were especially dedicated to the first problem and adequate solutions were proposed. The second problem have not received so much attention. However, there is a need to apprehend complex structures interconnecting dimensions and facts in various ways. We propose in this paper a model which permits to share dimensions at different levels between different Acts and to describe various relationships between facts. We then define the notion of well forms for warehouse structures.