Designing a Data Warehouse: Supporting Customer Relationship Management

FIRST-GENERATION SOLUTIONS FOR TIME

We now go on to describe some solutions to the problems of the representation of time that have been used in first-generation data warehouses.

One of the main problems is that the business requirements with respect to time have not been systematically captured at the conceptual level. This is largely because we are unfamiliar with the temporal semantics due to the fact that, so far, we have not encountered temporal applications.

Logical models systematically follow conceptual models, and so a natural consequence of the failure to define the requirements in the conceptual model is that the requirements are also absent from the logical and physical implementation. As a result, practitioners have subsequently ...