  In this paper, we study the data warehouse modelling used in decision support
systems. We provide an object-oriented data warehouse model allowing data
warehouse description as a central repository of relevant, complex and temporal
data. Our model integrates three concepts such as warehouse object, environment
and warehouse class. Each warehouse object is composed of one current state,
several past states (modelling its detailed evolutions) and several archive
states (modelling its evolutions within a summarised form). The environment
concept defines temporal parts in the data warehouse schema with significant
granularities (attribute, class, graph). Finally, we provide five functions
aiming at defining the data warehouse structures and two functions allowing the
warehouse class inheritance hierarchy organisation.
