I usually don’t read books with step by step instruction like “click File, then click Open”. I start working with a new tool right away and months later I start looking for a book to fill the gaps in my knowledge and experience. This book partially is based on such step by step instructions (duplicated for both Excel and Power BI). It’s the only book in my library with such instructions and I had to skip most of them. They are probably great for someone who is starting to work with Power Query, but I started a long time ago. Despite that fact I’m really happy that I bough this book.
It’s not a manual for someone who just opened Power Query. It’s a book of good methods and best practices explained on a level that will be accessible for anyone from a student to an expert. The book is a deep dive into data preparation challenges, appending, merging, pivoting and unpivoting, advanced text analysis. It’s a good introduction into M language from a practical point of view (which include error handling, loops and recursions /you’ll need them for most API connections/). It’s a book about challenges and pitfalls. Must have for anyone who want to make sure he is ready to meet data transformation challenges and who want to know how to avoid pitfalls. Data preparations is a very important step. If you did it wrong – you won’t be able to build a good data model (star schema), you won’t be able to build an insightful data visualization. Read the book and get the value out of the data.
Buy the book: Collect, Combine, and Transform Data Using Power Query in Excel and Power BI (Amazon.co.uk link, I’m in Europe and this where I got the book. I believe you can find it on amazom.com as well). I left the same review on amazon.co.uk. It’s just my opinion as is about the book that I bought and read, I’m not affiliated with the author, the publisher or Amazon in any way.