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

Creating fact tables

Now that we've created all the dimensions, it is time to create a fact table that contains numeric values and the primary keys of the dimensions as foreign keys. Looking at the Sales Base and Customer Base data shows us that the Sales Base table holds many transactions with numeric values. Therefore, a fact table can be derived from the Sales Base table, which we will call Sales, by following these steps:

  1. Reference the Sales Base table and then rename the new table Sales.

    We want to get ProductKey from the Product table. To do so, we can merge the Sales table with the Product table.

  2. Click Merge Queries.
  3. Select the ProductCategory, ProductSubcategory, and Product columns, respectively.
  4. Select the Product table from the dropdown list.
  5. Again, select the ProductCategory, ProductSubcategory, and Product columns.
  6. Select Left outer (all from first, matching from second) from the Join Kind dropdown list.
  7. Click OK:

    Figure 6.37 –...