The Data Warehouse Lifecycle Toolkit

xxxii Introduction

warehouse. And conversely, a data warehouse without business intelligence

will fail spectacularly.

This book is a relentlessly practical field guide for designers, managers, and

owners of the DW/BI system. We have tried to distinguish this book from

other DW/BI books by making the content very concrete and actionable. It’s

okay to be dazzled by the landscape but we want you to make it all the way to

the finish line. This book describes a coherent framework that goes all the way

from the original scoping of an overall enterprise DW/BI system, through the

detailed steps of developing and deploying, to the final steps of planning the

next phases.

There are tens of thousands of functioning data warehouse installations

across the world. Many DW/BI owners have developed a complete lifecycle

perspective. Probably the biggest insightthatcomesfromthisperspectiveis

that each DW/BI system is continuously evolving and dynamic. It cannot

be static. It never stops transforming. New business requirements arise. New

managers and executives place unexpected demands on the system. New data

sources become available. At the very least, the DW/BI system needs to evolve

as fast as the surrounding organization evolves. Stable organizations will place

modest demands on the system to evolve. Dynamic, turbulent organizations

will make the task more challenging.

Given this churning, evolving nature of the DW/BI system, we need design

techniques that are flexible and adaptable. We need to be half DBA and half

MBA. We need to opportunistically hook together little pieces from individual

business processes into larger pieces, making enterprise data warehouses. And

we need our changes to the system always to be graceful. A graceful change is

one that doesn’t invalidate previous data or previous applications.

How this Book is Organized

This book has two deep underlying themes. The first is the Kimball Lifecycle

approach. You might ask ‘‘What makes the Kimball Lifecycle different from

any other methodology?’’ The shortest answer is that we build DW/BI systems

by starting with the business users and figuring out what they need to do

their jobs. Then, with those results in mind, we systematically work backward

through the reports, applications, databases, and software, finally arriving at

the most physical layers of the implementation. This contrasts strongly with

technology driven approaches, which proceed in the opposite direction. In

the early days of the 1990s, some IT shops didn’t know what to make of our

business and user oriented approach. But as we publish this book in 2008, the

very name ‘‘business intelligence’’ says it all. The user and the business drive

the data warehouse.

The second theme is the ‘‘bus architecture.’’ We will show you how to

build a succession of individual business process iterations that will, in time,