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daxesh
Helper I
Helper I

DAX Measure performance

Hello,

Below are some of measures :
1. Count of student = COUNT(Fact[StudentId])
2. Status = IF([Count of student] =1,"One",IF([Count of student]=2,"two","None"))

(Please do not take above formuls's in business logic context , These are just drafted to understand a question.)

 

If you review above formulas, [Status] is using [Count of student] multiple time.
I am wondering : Will Power BI engine calculate [Count of student] once or multiple times as it occurs multiple time in [Status] ?

 

This is related to measure performance optimisation.Above scenario is a imitation of original formula i am using. If inner measure is getting calculated every time it appears in parent formula then there'll be certain performance drop , Right?

 

Do Power BI engine handling such scenario that if inner measure is occuring multiple times in parent measure then calculate it once only OR it will get multiple times?

 

thanks

 

 

1 REPLY 1
Greg_Deckler
Super User
Super User

It's an interesting question, but not sure how meaningful it is. The alternative would be to use COUNT(Fact[StudentId]) in your second formula in place of [Count of student] and at that point, you are certainly calculating it multiple times so...


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