Is Measure Branching a good idea for report performance

[Anonymous]

I have avoided using referencing measures inside other measures (Measure branching) because I heard from somewhere that was a bad idea (I don't remember where). But there seems to be a few including Enterprise DNA who think it is a good idea. I couldn't anything official from Microsoft that says this a good for performance. I plan on installing DAX Studio when my IT department adds it to the software whitelist so I can test it myself. But I was hoping to get confirmation from more sources that measure branching is a good idea before using it. 

[Jihwan_Kim]

In my opinion, it is not a good idea when it references measures ( or references measures that already referenced other measures) that have ALLSELECTED function as a CALCULATE modifier (inside the CALCULATE function).

I only know the above case that I need to double-check and audit the result of the measure every time.

Other than the above, I still need to learn and study whether there are any other cases that make Measure Branching not a good idea.

[Fowmy · Accepted solution]

@Anonymous 

It depends 🙂

When you create a measure, it is wrapped in a CALCULATE function. It depends where you want to use it. If you do not need a context transition to happen for example in a row context then do not use measure there. However, Measure Branching, in general, doesn't affect the performance, it will is the same. I heard it from Marco Russo as well. 

[Anonymous]

So if I use CALCULATE then don't use that measure in another measure? Do you know where you heard it from Marco Russo? I am only 7 chapters in The Definitive Guide to DAX 2nd edition. I didn't see anything specific for measure branching in the contents. 

[Fowmy]

@Anonymous 

No, I did not mean that way. You can use a measure inside another measure, all I meant was a measure is always wrapped within a calculate function, so when you use it inside another calculation, it will create context transition. I just stressed this point. So, you can use a measure inside another as long as you are aware of the context. 

The following video explains the nested calculate usage:   @marcorusso 

https://www.youtube.com/watch?v=hZd9EgUR7Do&t=3580s