The Data Warehouse Toolkit: The Complete Guide to Dimensional Modeling

Chapter 10. Telecommunications and Utilities

This chapter will flow a bit differently than preceding chapters. We'll still begin with a case study overview, but we won't be designing a dimensional model from scratch this time. Instead, we'll step into a project midstream to conduct a design review, looking for opportunities to improve the initial draft schema. Do you recall reading Highlights for Children magazine in your dentist's waiting room long ago? If so, do you remember the what's wrong with this picture worksheets where you identified all the out-of-place items, like the chicken driving a car or a snowman on the beach? The bulk of this chapter will focus on a dimensional modeling what's wrong with this picture exercise where we'll identify out-of-place design flaws.

We'll use a billing vignette drawn from the telecommunications industry as the basis for the case study; however, it shares similar characteristics with the billing data generated by a utilities company. At the end of this chapter we'll elaborate on managing and leveraging the geographic location information in the warehouse, regardless of the industry.

Note

Chapter 10 discusses the following concepts:

• Design review exercise

• Common design mistakes to look for in a review

• Geographic location dimension, including its treatment as a snowflaked outrigger and its interaction with geographic information systems

Telecommunications Case Study

Given your extensive experience in dimensional modeling (nine chapters so far), you've ...