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Anonymous's avatar
Anonymous
Not applicable
4 years ago
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Power BI Optimization

There is a lot of documentation about when to use DAX Measures vs DAX calculated columns. However, in what instances would it make sense to create a calculated column in the source i.e. SQL vs creati...
  • Applicable88's avatar
    4 years ago

    Anonymous,   measures are computed at runtime and calculated columns needs to be stored. That means measures does not need storage space, but the latter do. They also tend to make your calculation slower, since your model grow with the columns generated. Thats the reason when possible to use measures. They are only computed when you need them. Anyway, a good reason for the need of a calculated column might be the need for a "customize" dimension that you need for a bar chart. For example your mastercalendar doesn't consist of a weeknumber to the date, than you need to create one with weeknumber() - function. And now go further that you want to to have a bar chart dimension, where your calendar week is concatenated with the year number together á la " 2021 / 40 " . If you want a customized dimension you need a calculated column for that. You cannot drag a measure into a bar chart visual as a dimension. 

    I hope that helps.