Before getting to deep dive into the simplest way to learn DAX, let’s discuss about DAX and the importance of DAX first.
What is DAX?
Data Analysis Expressions (DAX) is a library or collection of functions, operators, and constants that can be used in a formula, or expression, to calculate and return one or more values in Power BI Desktop, Azure Analysis Services, SQL Server Analysis Services, and Power Pivot in Excel. In simple language, we can say that DAX helps us in creating new information from data already in our model.
Why is DAX so important?
It’s easy to create a new Power BI Desktop file and import some data into it from any of the source (e.g. Excel, MS Access, SQL, etc.). It is also very easy to create reports/dashboard in Power BI without using a single DAX formula. But we start facing challenges when we need to analyze critical data, related data elements in the model and for different date ranges. To deal with such complex scenarios and derive the required insights from business data, DAX formulas provide this capability and many other important capabilities as well. It is advisable to learn DAX so that you can create effective DAX formulas that will help you get the most out of your data. When you get the information you need, you can begin to solve real business problems that affect your bottom line. This is Business Intelligence, and DAX will help you get there.
As we are pretty much familiar with DAX and its importance, let’s start focusing on the best way to learn it. Here, we will consider both paid and free resources to get expertise in mastery of DAX language. All the points mentioned below are in sequential order and based on our learning experience.
Step 1 – Microsoft Guided Learning – Introduction to DAX
Follow the below guided learning program by Microsoft to learn DAX basics and fundamentals – how to think about DAX, how it works, and the most useful features as explained (and learned with lots of experiences) by a renowned DAX expert, Alberto Ferrari.
The videos in this Guided Learning program on DAX teach you DAX basics from the perspective of how the DAX formula language works. This is useful when creating DAX formulas from scratch, but it’s also very useful for understanding how Power BI creates those DAX formulas as you create queries in the Query Editor.
Follow the below link to jump to the Guided Learning program on DAX.
Step 2 – Free sample of the book ‘The Definitive Guide to DAX’
Great work by Marco and Alberto. We would like to thank the authors who came up with this book and to explain the concepts in such a detail. The complete version of this is most exhaustive book for mastering DAX. Remember, it is not for a casual Excel user and one must put in a lot of effort to understand DAX and practically implement the same while reading all chapters of this book. And, this is the reason we have picked the sample book to start your DAX journey. This book has total 20 chapters and sample covers only first 8 chapters which are enough for a good start and strong foundation for DAX and Power BI journey.
Below are the chapters available in sample book. Please learn each chapter very carefully and try to understand it, practice all the examples on data-sets for complete understanding.
- Chapter 1 – What is DAX?
- Chapter 2 – Introducing DAX
- Chapter 3 – Using basic table function
- Chapter 4 – Understanding evaluation contexts
- Chapter 5 – Understanding CALCULATE and CALCULATETABLE
- Chapter 6 – Variables
- Chapter 7 – Working with iterators and with CALCULATE
- Chapter 8 – Time intelligence calculations
First 3 chapters are very important for basic understanding of DAX. So, read it again and again till you don’t understand the technicality. Once you complete the first 3 chapters, move to the ‘Evaluation Contexts’ the chapter 4. This is one of the complex and critical concepts of DAX. You need to thoroughly understand several subtle considerations and details. Otherwise, you will feel lost at certain point on your DAX learning path. You should not hesitate to come back to the Chapter 4 and read it again to clear your doubts and find something new that you missed during your first read. This happens with everyone who starts DAX journey.
After completing first 4 chapters, read rest of the 4 chapters carefully and do all the exercises what authors have suggested. Don’t be hurry, take your time to understand this language.
You can download free sample from the Amazon and Google Play.
Step 3 – Watch exclusive DAX tutorials on YouTube
We have compiled the list of some of the best tutorials available on YouTube by DAX gurus. We are thankful to creators and YouTube channel owners to provide such a good tutorial on DAX.
Remember, you must have completed at least 4 chapters from the sample book ‘The Definitive Guide to DAX’ before watching these tutorials. You will be able relate the technical terms and learn it in effective way if you do so.
Please watch the tutorials in sequential way and don’t skip it. You may explore other YouTube videos after completing these tutorials.
Disclaimer: we don’t own any rights on these videos. We provided the link of videos for learning purpose and all the descriptions of videos have been taken from the descriptions available for respective videos on YouTube.
In this two-hours workshop, you learn the basics of the DAX language. Alberto will introduce you to the concept of calculated columns, measures, basic data modeling with some practical examples that you will be able to reproduce on the hands-on-lab PC. This introduction covers basic calculations and an overview of all the scalar and table functions in DAX.
2. Advanced DAX
This session is a natural continuation of “DAX 101” and aims to teach you some of the advanced features of DAX. Alberto will explain in detail the concepts of filter context and row context, which are the pillars of DAX. After some (much needed) theory, you will use this knowledge to create a set of calculations, mainly related to time-intelligence, using the hands-on-lab PCs.
Everyone struggled with evaluation context while creating formulas in DAX. It has happened to us many times, and we know that the problem is ALWAYS related to the evaluation context. Filter context, row context, and context transition are only the starting point of a deep dive into how DAX computes the evaluation context for a formula. See several examples of formulas that lead to unexpected results and learn the unifying theory of evaluation contexts based on expanded tables, filter context operators, and blocking semantic. If you are serious about DAX, this session is a real must.
Time Intelligence is probably the most interesting feature of any analytical solution. Computing Year-To-Date, Month-To-Date, Same-Period-Last-Year, is quite easy in DAX but, as soon as the customer requests for time intelligence comparing data from different tables, or to manage non-standard calendars, the DAX formulas start to be harder to write.
In this session, you will learn how to compute classical time intelligence with the built-in Power BI tools and DAX functions. Then, you will learn some more complex time intelligence formulas, which require thinking out of the box, using advanced data modeling and querying techniques to produce interesting and useful formulas.
Step 4 – Start creating reports/dashboard in Power BI
Start creating reports/dashboard in Power BI and utilize all the DAX expressions and tips you learnt it so far. Download practice raw data from internet. Google it to find data for Power BI practice.
You can also refer the below mentioned sites and bookmark these for your quick reference. These sites will work like a DAX dictionary for you.
You can also take help from Microsoft Power BI community to Connect, learn and discuss with business intelligence experts and peers. Refer all the relevant questions and answers for your query. Ask your question if it’s not available there.
Don’t forget to upvote the answer if you find what you are looking for. This will keep Power BI community motivated. 🙂
Step 5 – Full version of ‘The Definitive Guide to DAX’
Now, you are comfortable with DAX and have started creating interesting report and dashboard in Power BI with several insights and analytics. This is the time to move to the next level and buy the full version of ‘The Definitive Guide to DAX’. Make sure to buy second edition only. Trust me, you will love this book and get the master in DAX after completing it.
As you have already completed first 8 chapters, you can move from the Chapter 9 as mentioned below but I will strongly recommend you to quickly go through the Chapter 1 to 8 for revision purpose.
- Chapter 9 – Calculation groups
- Chapter 10 – Working with filter contexts
- Chapter 11 – Handling hierarchies
- Chapter 12 – Working with tables
- Chapter 13 – Authoring queries
- Chapter 14 – Advanced DAX concepts
- Chapter 15 – Advanced relationships
- Chapter 16 – Advanced calculations in DAX
- Chapter 17 – The DAX engines
- Chapter 18 – Optimizing VertiPaq
- Chapter 19 – Analyzing DAX query plans
- Chapter 20 – Optimizing DAX
Note: this suggestion is purely based on our experience and there is no affiliated account associated with any of the link provided in this article.
Hope, you find this post useful and will help you in your DAX learning journey. You can find several articles on DAX and Power BI on our site thedatalabs.org. Please do visit to our Power BI section to learn more tips and tricks.
Please leave a comment if you are looking for any clarifications and have a question on that. Our team will happy to assist you.