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

Summary

In this chapter, we’ve covered several crucial techniques to enhance the performance of your Power Query workflows.

We began by emphasizing the importance of efficient data filtering and reduction, encouraging you to remove unnecessary data early in your query. We explored the use of native M functions, highlighting their efficiency compared to custom code for specific tasks. Optimizing custom functions was the next focus; we learned to optimize calculations not covered by native functions. The chapter also touched on the significance of optimizing memory usage, introducing Table.Buffer and other memory-efficient coding practices.

We then delved into the game-changing concept of parallel query execution, showcasing how functions such as Table.Split can drastically reduce query execution times by dividing large tables into smaller partitions and enabling parallel processing. These techniques will empower you to tackle complex data transformation tasks in Power BI...