Book Image

Data Cleaning with Power BI

By : Gus Frazer
Book Image

Data Cleaning with Power BI

By: Gus Frazer

Overview of this book

Microsoft Power BI offers a range of powerful data cleaning and preparation options through tools such as DAX, Power Query, and the M language. However, despite its user-friendly interface, mastering it can be challenging. Whether you're a seasoned analyst or a novice exploring the potential of Power BI, this comprehensive guide equips you with techniques to transform raw data into a reliable foundation for insightful analysis and visualization. This book serves as a comprehensive guide to data cleaning, starting with data quality, common data challenges, and best practices for handling data. You’ll learn how to import and clean data with Query Editor and transform data using the M query language. As you advance, you’ll explore Power BI’s data modeling capabilities for efficient cleaning and establishing relationships. Later chapters cover best practices for using Power Automate for data cleaning and task automation. Finally, you’ll discover how OpenAI and ChatGPT can make data cleaning in Power BI easier. By the end of the book, you will have a comprehensive understanding of data cleaning concepts, techniques, and how to use Power BI and its tools for effective data preparation.
Table of Contents (23 chapters)
Free Chapter
1
Part 1 – Introduction and Fundamentals
6
Part 2 – Data Import and Query Editor
11
Part 3 – Advanced Data Cleaning and Optimizations
16
Part 4 – Paginated Reports, Automations, and OpenAI

Creating custom functions

With proper planning and an understanding of parameters, you’re now ready to dive into creating custom functions in Power Query. This section will guide you through the process of building your custom function, including defining its structure, working with M code, and testing your function.

Defining the function structure

The structure of your custom function is crucial for its functionality and usability. Define the following aspects of your function:

  • Name: Choose a descriptive name for your function
  • Parameters: Specify the parameters your function will accept and their data types
  • Description: Provide a clear and concise description of what your function does
  • Result: Determine the expected result or output of your function

Writing M code

Power Query functions are created using the M language, which we touched upon earlier in this book. You’ll need to write M code to define your function’s behavior...