Forum Discussion
DirectQuery to AAS: Measures return Blank instead of Error after Refresh (Silent Failure?)
Hi rohit1991 ,
Thanks for reply me soon!
Since this "known DirectQuery limitation" is rarely documented explicitly in the official Microsoft documentation, I would love to learn more about where this knowledge comes from.
I am trying to improve my own ability to troubleshoot these types of backend limitations. Could you share what key reading materials, or technical blogs led you to this conclusion?
Additionally, regarding the Measure B formula you provided:
Measure B :=
IF (
NOT ISBLANK ( [Measure_from_AAS] ),
DIVIDE ( [Measure_from_AAS], [Measure_A] )
)Does this imply that for DIVIDE() to "explicitly guard" the measure and prevent a collapse, the underlying mechanism is effectively forced to act like an IF() statement? In other words, when the model hits its performance limit, does it return a BLANK as a protection mechanism instead of throwing a MemoryLimit?
Is this "silent blank" actually a sign of insufficient hardware resources on the AS side.
Thanks again for sharing your expertise!
v-veshwara-msftCommunity Support
Hi WangHsuanHui ,
Thank you for the follow up.
The earlier explanation by rohit1991 is directionally correct.
Microsoft documentation confirms that DirectQuery and composite models have limitations and that query execution in the Service can differ from Desktop due to optimization and planning differences. In complex composite scenarios, results after a scheduled refresh may not always behave consistently.
DirectQuery in Power BI: When to Use, Limitations, Alternatives - Power BI | Microsoft Learn
Use composite models in Power BI Desktop - Power BI | Microsoft Learn
The guarded DIVIDE pattern does not change the internal behavior of DIVIDE, but it can alter the query evaluation path and reduce dependency chaining, which may avoid unstable query plans in some DirectQuery scenarios. This should be considered a mitigation rather than a guaranteed fix.
There are also community discussions that describe how caching and metadata handling can affect composite model behavior in the Service, particularly after refresh.
For example: Solved: Composite model - not able to refresh when I have ... - Microsoft Fabric Community
Hope this helps. Please reach out for further assistance.
Thank you.- v-veshwara-msft
Hi WangHsuanHui ,
Just wanted to check if the response provided was helpful. If further assistance is needed, please reach out.
Thank you.