Calculate Column Vs Custom Column in Power BI

Question

In Power BI Desktop, I have the option to add a calculated column in a Model view using DAX expression from Mdeling Tab as below

However, I can also add a custom column in Power Query Editor when transforming data as below

What're the main differences between the Calculated Column in Model view and the Computed Column in Power Query Editor, and Which one should I use in Power BI?

Answer 1

Main differences between Calculate Column Vs Custom Column in Power BI

Whatever you will use Calculated Column or Custom Column, the final result will be the same!

So in general, it doesn't matter and when you have the option to add Calculate Column or Custom Column, you should first consider the simple and faster way that best matches your skills.

However, it's recommended to add Computed Columns in Power Query, whenever possible, because they load to the model in a more compact and optimal way than the calculated column. Read more at Power BI: Custom Column Vs Calculated Column

Below are some considerations when you add a new column in your model in Power BI

Custom Column

• When you add a Custom Column in Power Query Editor, you have to use M language.
• Creating a new Custom Column or even performing bit changes on the currently created Custom Column requires more time depends on the table size because it needs a full refresh of the table.
• The size of the Custom Column in Power Query is always smaller than the created Calculated Column in DAX.
• You can’t use DAX expressions in a Custom Column in Power Query Editor.

Calculated Column

• When you add a Calculated Column in Data View or Report View, you have to use DAX.
• Creating a new DAX Calculated Column is faster because it does not require a full refresh of the table.
• The size of the DAX Calculated Column is always bigger than the created Custom Column in Power Query.
• You can’t use M language in a Calculated Column in Report or Data View in Power BI.

For more details, Please check When you should use Calculate Column Vs Custom Column in Power BI?

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See Also

• Power BI: Custom Column Vs Calculated Column
• Main differences between DAX Vs M Language.

Comments

The attached link and answer are very helpful, Thank you!