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
1
Cover
2
Title Page
3
Copyright
4
About the Authors
5
Credits
6
Acknowledgements
29
Index
30
Advertisement
31
End User License Agreement

Extracting: Getting Data into the Data Warehouse

To no surprise, the initial subsystems of the ETL architecture address the issues of understanding your source data, extracting the data, and transferring it to the data warehouse environment where the ETL system can operate on it independent of the operational systems. Although the remaining subsystems focus on the transforming, loading, and system management within the ETL environment, the initial subsystems interface to the source systems for access to the required data.

Subsystem 1: Data Profiling

Data profiling is the technical analysis of data to describe its content, consistency, and structure. In some sense, any time you perform a SELECT DISTINCT investigative query on a database field, you are doing data profiling. There are a variety of tools specifically designed to do powerful profiling. It probably pays to invest in a tool rather than roll your own because the tools enable many data relationships to be easily explored with...