Book Image

The Data Warehouse Toolkit - Third Edition

By : Ralph Kimball, Margy Ross
5 (1)
Book Image

The Data Warehouse Toolkit - Third Edition

5 (1)
By: Ralph Kimball, Margy Ross

Overview of this book

The volume of data continues to grow as warehouses are populated with increasingly atomic data and updated with greater frequency. Dimensional modeling has become the most widely accepted approach for presenting information in data warehouse and business intelligence (DW/BI) systems. The goal of this book is to provide a one-stop shop for dimensional modeling techniques. The book is authored by Ralph Kimball and Margy Ross, known worldwide as educators, consultants, and influential thought leaders in data warehousing and business intelligence. The book begins with a primer on data warehousing, business intelligence, and dimensional modeling, and you’ll explore more than 75-dimensional modeling techniques and patterns. Then you’ll understand dimension tables in-depth to get a good grip on retailing and moved towards the topics of inventory. Moving ahead, you’ll learn how to use this book for procurement, order management, accounting, customer relationship management, and many more business sectors. By the end of this book, you’ll be able to gather all the essential knowledge, practices, and patterns for designing dimensional models.
Table of Contents (31 chapters)
Free Chapter
Title Page
About the Authors
End User License Agreement

Common Dimensional Modeling Mistakes to Avoid

As we close this final chapter on dimensional modeling techniques, we thought it would be helpful to establish boundaries beyond which designers should not go. Thus far in this book, we’ve presented concepts by positively stating dimensional modeling best practices. Now rather than reiterating the to-dos, we focus on not-to-dos by elaborating on dimensional modeling techniques that should be avoided. We’ve listed the not-to-dos in reverse order of importance; be aware, however, that even the less important mistakes can seriously compromise your DW/BI system.

Mistake 10: Place Text Attributes in a Fact Table

The process of creating a dimensional model is always a kind of triage. The numeric measurements delivered from an operational business process source belong in the fact table. The descriptive textual attributes comprising the context of the measurements go in dimension tables. In nearly every case, if an attribute is used...