Book Image

The Data Warehouse Toolkit - Third Edition

By : Ralph Kimball, Margy Ross
Book Image

The Data Warehouse Toolkit - Third Edition

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

Clickstream Source Data

The clickstream is not just another data source that is extracted, cleaned, and dumped into the DW/BI environment. The clickstream is an evolving collection of data sources. There are a number of server log file formats for capturing clickstream data. These log file formats have optional data components that, if used, can be very helpful in identifying visitors, sessions, and the true meaning of behavior.

Because of the distributed nature of the web, clickstream data often is collected simultaneously by different physical servers, even when the visitor thinks they are interacting with a single website. Even if the log files collected by these separate servers are compatible, a very interesting problem arises in synchronizing the log files after the fact. Remember that a busy web server may be processing hundreds of page events per second. It is unlikely the clocks on separate servers will be in synchrony to one-hundredth of a second.

You also obtain clickstream...