Book Image

Expert Data Modeling with Power BI

By : Soheil Bakhshi
Book Image

Expert Data Modeling with Power BI

By: Soheil Bakhshi

Overview of this book

This book is a comprehensive guide to understanding the ins and outs of data modeling and how to create data models using Power BI confidently. You'll learn how to connect data from multiple sources, understand data, define and manage relationships between data, and shape data models to gain deep and detailed insights about your organization. In this book, you'll explore how to use data modeling and navigation techniques to define relationships and create a data model before defining new metrics and performing custom calculations using modeling features. As you advance through the chapters, the book will demonstrate how to create full-fledged data models, enabling you to create efficient data models and simpler DAX code with new data modeling features. With the help of examples, you'll discover how you can solve business challenges by building optimal data models and changing your existing data models to meet evolving business requirements. Finally, you'll learn how to use some new and advanced modeling features to enhance your data models to carry out a wide variety of complex tasks. By the end of this Power BI book, you'll have gained the skills you need to structure data coming from multiple sources in different ways to create optimized data models that support reporting and data analytics.
Table of Contents (18 chapters)
Section 1: Data Modeling in Power BI
Section 2: Data Preparation in Query Editor
Section 3: Data Modeling
Section 4: Advanced Data Modeling

Identifying dimensions and facts

When we are talking about a Star Schema, we are automatically talking about dimensions and facts. In a Star Schema model, we usually keep all the numeric values in fact tables and put all the descriptive data in the Dimension tables. But not all numeric values fall into fact tables. A typical example is Product Unit Price. If we need to do some calculations regarding the Product Unit Price, it is likely a part of our fact table. However, if the Product Unit Price is used to filter or group the data, it is probably a part of a dimension.

Designing a data model in a Star Schema is not possible unless we have a level of understanding of the data. This chapter aims to look at the Chapter 6, Sales Data.xlsx data and create a Star Schema.

As we mentioned earlier, to create a Star Schema, we need to have a closer look at the data we are going to model and identify dimensions and facts. In this section, we will try to find these dimensions and facts...