DAX or M language, what am I doing?

[plerner]

I don't understand when I am suppose to be using DAX or the M language. I read a lot of documentation and it is not clear to me. In a lot of places DAX is mentioned as the language to create formulas, new columns and filters in Power BI, but when I look for information in a specific formula I always end up looking at the M language reference. So, can anyone, please, help me understand what is going on between those two?

[Rfranca · Accepted solution]

@plerner

see the link below ...

https://community.powerbi.com/t5/Desktop/Dax-or-M-Language/td-p/136827

[MarcelBeug · Accepted solution]

In general, Power Query (or M) is an ETL (Extraction, Transformation, Load) tool, so it gets data and transforms it into tables that can be be loaded and structured in a datamodel.

Next, DAX kicks in for further data analysis, typically aggregation into measures and results that may depend on filter contexts.

There is a large grey area in which both Power Query and DAX can be used.

Typically, DAX is most populair, so you will find most DAX solutions on this forum.

Also, the Power Query documentation is not very clear, incomplete and sometimes even wrong.
Apparently it doesn't have the highest priority.

You can find an interesting Power Query (M) functions dashboard in the Data Stories gallery.

You may guess correctly that Power Query is my specialty.

[Rfranca · Accepted solution]

@plerner

see the link below ...

https://community.powerbi.com/t5/Desktop/Dax-or-M-Language/td-p/136827