Book Image

Expert Data Modeling with Power BI - Second Edition

By : Soheil Bakhshi
4 (1)
Book Image

Expert Data Modeling with Power BI - Second Edition

4 (1)
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 full-fledged data models using Power BI confidently. In this new, fully updated edition, 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. As you advance through the chapters, the book will demonstrate how to prepare efficient data models in the Power Query Editor and use simpler DAX code with new data modeling features. You'll explore how to use the various data modeling and navigation techniques and perform custom calculations using the modeling features with the help of real-world examples. 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. Additionally, you'll learn valuable best practices and explore common data modeling complications and the solutions to supercharge the process of creating a data model in Power BI and build better-performing data models. 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 high-performing reports and data analytics.
Table of Contents (22 chapters)
1
Section I: Data Modeling in Power BI
4
Section II: Data Preparation in Query Editor
10
Section III: Data Modeling
13
Section IV: Advanced Data Modeling
20
Other Books You May Enjoy
21
Index

Avoiding bidirectional relationships

One of the most misunderstood and somehow misused Power BI features in data modeling is setting the Cross filter direction to Both. This is widely known as a bidirectional relationship. There is nothing wrong with setting a relationship to bidirectional if we know what we are doing and are conscious of its effects on the data model. We have seen Power BI developers who have many bidirectional relationships in their model and consequently end up with many issues, such as getting unexpected results in their DAX calculations or being unable to create a new relationship due to ambiguity.

The reason that overusing bidirectional relationships increases the risk of having an ambiguous model is filter propagation. In Chapter 8, Data Modeling Components, we covered the concept of filter propagation and bidirectional relationships. We looked at a scenario where the developer needed to have two slicers on a report page, one for the product category and...