Adding a Calculated Column in Semantic Model

[JaviGolden]

I am trying to replicate a power bi "desktop" model in a fabric lakehouse.   I have a lakehouse with all the tables loaded and I've created a semantic model.   I need to create some calculated columns based on lookups to tables within the model, however, the "New Column" functionality is not available.  

Am I trying to do this in the wrong place or is there something that I need to configure to allow this functionality?   

Thx!

[blopez11 · Accepted solution]

This is not currently supported for semantic models derived from a lakehouse.

Please see: Learn about Direct Lake in Power BI and Microsoft Fabric - Microsoft Fabric | Microsoft Learn

As an option, you can create them in your lakehouse.

[aanchalvazir]

Hi @JaviGolden, this feature is now supported with the April 2026 Power BI update, although still in preview.
Please check the Microsoft blog: Power BI April 2026 Feature Summary | Microsoft Power BI Blog | Microsoft Power BI

Hope this helped!

[blopez11 · Accepted solution]

No, I don't believe you can use DAX.  I was thinking how ever you created your lakehouse, like if you used Gen2 dataflows, you could replicate the logic.

[blopez11 · Accepted solution]

This is not currently supported for semantic models derived from a lakehouse.

Please see: Learn about Direct Lake in Power BI and Microsoft Fabric - Microsoft Fabric | Microsoft Learn

As an option, you can create them in your lakehouse.

[rsheltondavid]

Trying the same here, did you create the calculated columns using notebooks and add them to the lakehouse tables? Please let me know as i am currently trying to do the same. @blopez11 @JaviGolden 

[blopez11]

Depending on my scenario, I used either dataflows gen2 or notebooks to create new lakehouse tables/columns.

[JaviGolden]

Thx.  Can you use Dax in the lakehouse to do the lookups?   I've not been able to figure that out.