Renowned DAX experts Alberto Ferrari and Marco Russo teach you how to design data models for maximum efficiency and effectiveness.

How can you use Excel and Power BI to gain real insights into your information? As you examine your data, how do you write a formula that provides the numbers you need? The answers to both of these questions lie with the data model. This book introduces the basic techniques for shaping data models in Excel and Power BI. It’s meant for readers who are new to data modeling as well as for experienced data modelers looking for tips from the experts. If you want to use Power BI or Excel to analyze data, the many real-world examples in this book will help you look at your reports in a different way―like experienced data modelers do. As you’ll soon see, with the right data model, the correct answer is always a simple one!

By reading this book, you will:

• Gain an understanding of the basics of data modeling, including tables, relationships, and keys

• Familiarize yourself with star schemas, snowflakes, and common modeling techniques

• Learn the importance of granularity

• Discover how to use multiple fact tables, like sales and purchases, in a complex data model

• Manage calendar-related calculations by using date tables

• Track historical attributes, like previous addresses of customers or manager assignments

• Use snapshots to compute quantity on hand

• Work with multiple currencies in the most efficient way

• Analyze events that have durations, including overlapping durations

• Learn what data model you need to answer your specific business questions

About This Book

• For Excel and Power BI users who want to exploit the full power of their favorite tools

• For BI professionals seeking new ideas for modeling data

Table of Contents

Chapter 1 Introduction to data modeling

Chapter 2 Using header/detail tables

Chapter 3 Using multiple fact tables

Chapter 4 Working with date and time

Chapter 5 Tracking historical attributes

Chapter 6 Using snapshots

Chapter 7 Analyzing date and time intervals

Chapter 8 Many-to-many relationships

Chapter 9 Working with different granularity

Chapter 10 Segmentation data models

Chapter 11 Working with multiple currencies

Appendix A: Data modeling 101

About the Authors

Alberto Ferrari started working with SQL Server in 2000 and immediately his interest focused on Business Intelligence. He and Marco Russo created sqlbi.com, where they publish extensive content about Business Intelligence.

Alberto published several books about Analysis Services, Power BI, and Power Pivot. He is a Microsoft MVP and he earned the SSAS Maestro title, the highest level of certification on Microsoft Analysis Services technology.

Today, Alberto's main activities are in the delivery of DAX and data modeling workshops for Power BI and Analysis Services all around the world. Alberto offers consulting services on large and complex data warehouses to provide assessments and validation of project analysis or to perform specific problem-solving activities.

Alberto is a well-known speaker at many international conferences, like PASS Summit, Sqlbits, and Microsoft Ignite. He loves to be on stage both at large events and at smaller user groups meetings, exchanging ideas with other SQL and BI fans. When traveling for work, he likes to engage with local user groups to provide evening sessions about his favorite topics. Thus, you can easily meet Alberto by looking up local Power BI user groups during scheduled courses.

Outside of SQLBI, most of Alberto's personal time is spent practicing video games, in the vain hope of eventually beating his son.

Marco Russo is a business intelligence consultant and mentor in Business Intelligence.

He is a founder of SQLBI (www.sqlbi.com), which provides mentoring and consulting on Business Intelligence based on Microsoft technologies. He has particular competence and experience in sectors like financial services, manufacturing, gambling, and commercial distribution.

Marco is a Microsoft MVP and an SSAS Maestro, the highest level of certification on Microsoft Analysis Services. In addition to his BI-related publications, he has authored books about .NET programming.

Today, Marco focuses his time with SQLBI customers, traveling extensively to train and consult on DAX and data modeling for Power BI and Analysis Services. Marco also teaches public classes worldwide.

Marco is also a speaker at international conferences such as Microsoft Ignite, PASS Summit, and SQLBits.