Keeping Up With the Times

Overview

This paper provides an approach to implementing one of the more demanding types of transformations: the dreaded Type 2 Slowly Changing Dimension (SCD). Although this technique may be applicable to other type of transformations, it is particularly useful for the Type 2 SCD. The focus of this paper is the Type 2 SCD, as it is the most effective and most commonly used variety. The Type 2 SCD provides an approach for completely and elegantly tracking history, while conforming to the dimensional model for optimal performance. Although Oracle9i Warehouse Builder (OWB) does not have "Built-in" support for SCD transformations, one can easily implement them within the OWB framework.