Chapter 11

Telecommunications

This chapter unfolds a bit differently than preceding chapters. We 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. The bulk of this chapter focuses on identifying design flaws in dimensional models.

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

Chapter 11 discusses the following concepts:

  • Bus matrix snippet for telecommunications company
  • Design review exercise
  • Checklist of common design mistakes
  • Recommended tactics when conducting design reviews
  • Retrofitting existing data structures
  • Abstract geographic location dimensions

Telecommunications Case Study and Bus Matrix

Given your extensive experience in dimensional modeling (10 chapters so far), you've recently been recruited to a new position as a dimensional modeler on the DW/BI team for a large wireless telecommunications company. On your first day, after a few hours of human resources paperwork and orientation, you're ready to get to work.

The DW/BI team is anxious for you to review its initial dimensional design. So far it seems the project is off to ...

Get The Data Warehouse Toolkit: The Definitive Guide to Dimensional Modeling, 3rd Edition now with the O’Reilly learning platform.

O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.