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

Replacing values

A critical part of data preparation is data cleansing. When it comes to data cleansing, replacing values is one of the most common transformation activities we perform. A simple example is where we have a description column in which the users of the source system enter free text data, and we would like to replace some part of the description with something else.

When we use the Power Query Editor UI to replace a value in a table, it uses the Table.ReplaceValue(table as table, OldValue as any, NewValue as any, Replacer as function, columnsToSearch as list) function behind the scenes. If we want to replace the value of a List, it uses the List.ReplaceValue(list as list, OldValue as any, NewValue as any, Replacer as function) function. Depending on the value's data type that we want to replace, the Replacer function can be either Replacer.ReplaceText or Replacer.ReplaceValue. The difference between the two is that we can use Replacer.ReplaceText to replace text...