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nmasimore
Helper I
Helper I

Creating a Column - Model Efficiency/Storage/Best Practice - DAX vs. PowerQuery?

Hello

 

I have a transaction table and a calendar table. The transaction table has a Datetime column, not a date column.... so I am creating a column in the transaction table called "Date" and it will contain strictly the date (no time).

 

In terms of model efficiency/data storage/best practice, should I create this column using PowerQuery or DAX?

 

Open-ended question: When is it better to create columns using Power Query? When is it better to create columns using DAX?

1 ACCEPTED SOLUTION
Syk
Super User
Super User

It's almost always better to create it in Power Query. You can read more about it here: https://www.sqlbi.com/articles/comparing-dax-calculated-columns-with-power-query-computed-columns/

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4 REPLIES 4
AllisonKennedy
Super User
Super User

@nmasimore , I agree with @Syk . If you can create it in Power Query (or even better at the data warehouse) then do so. I find that DAX is handy for creating calculated columns that require referencing multiple tables, but that shouldn't be a common requirement. 


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Thank you @AllisonKennedy !

Syk
Super User
Super User

It's almost always better to create it in Power Query. You can read more about it here: https://www.sqlbi.com/articles/comparing-dax-calculated-columns-with-power-query-computed-columns/

Thank you @Syk !

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