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VigilanteWang
New Member

Variables in DAX

Hi,

I'm looking at this page Guided Learning , it mentions: 

"Keep in mind that each time you reference a variable in your DAX expression, Power BI must recalculate its value according to your definition. For this reason, it's good practice to avoid repeating variables in your function."

 

But in the video, the professor says the variables will be only calculated once, that's the reason to use it in the first place.

 

Am I missing something here?

1 ACCEPTED SOLUTION
Phil_Seamark
Microsoft Employee
Microsoft Employee

Hi @VigilanteWang

 

The guided learning is wrong.  Variables will only be calculated once (per calculation) and if used multiple times can actually lead to performance improvements.

 

So don't shy away from variables.

 

Phil


To learn more about DAX visit : aka.ms/practicalDAX

Proud to be a Datanaut!

View solution in original post

1 REPLY 1
Phil_Seamark
Microsoft Employee
Microsoft Employee

Hi @VigilanteWang

 

The guided learning is wrong.  Variables will only be calculated once (per calculation) and if used multiple times can actually lead to performance improvements.

 

So don't shy away from variables.

 

Phil


To learn more about DAX visit : aka.ms/practicalDAX

Proud to be a Datanaut!

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