There are situations in which you want to use a ranking of rows based on one column, but that column has non-unique values. Sometimes, there are other columns you want to use, if two rows have the same value in the primary ranking column.  In this blog, I want to explain step by step how ranking based on multiple columns (more than 2!) can help you solve this problem in DAX. The pattern used is something I picked up in this community, the focus in this blog is on the inner workings of that pattern.

In this blog series I will set apart all the steps needed to get this demo up and running on your own. I will use the text in this post, as well as screenshots and videos explaining it step by step. So, if you're already (somewhat) familiar with Forms, Power Automate and/or Power BI streaming datasets, feel free to go directly to the videos and start building your own demo right away. Otherwise, keep reading and eventually you'll come across all the resources, as well.

Power BI has gone through many changes in 2019.  At PowerBI.Tips we've been following along with every new feature release.  So for the beginning of 2020 PowerBI.Tips would like to give  you the top Tips and Tricks of 2019 to enhance your reports. 

 Change Source in Power BI Desktop is disabled

Changing a Data Source connection in Power BI Desktop is very simple, just two or three clicks, as you can see in these two very simple methods:

Although it is a simple step to change the connection of a Data Source in Power BI Desktop, sometimes we face a problem that makes this change difficult, when the option button [Change Source ...] is disabled, which forces us to change manually within the Power Query Advanced Editor.

So, first we need to understand the logic that Power BI uses and why this option appears disabled. Everything happens within Power Query, as you can see, the first step we cannot exclude, precisely because Power BI understands that every first step of each query will be the Data Source. That is, if we start a query creating a variable instead of starting with the connection to the Data Source, the option to change the Data Source in the simple way you saw at the beginning of this article will be automatically disabled.

Conclusion:

What can we do to fix this problem? We need to create these variables in a separate query, so we can use these variables in any other Query and at any step of it, but not in the first, as you can see in the image below. Also, it is a good practice of queries organization.

So, the first step of Query will always be the Data Source and you will always have the option button to change the Data Source activated, because Power BI will always find your first stage of Query your Data Source.

Thank you for reading and give your feedback. 🙂