Forum Discussion
My DataFlow Gen 2 Fails with Unknown Evaluation Error 999999 (Request ID: fcd89914-0dd9-44ea-9b09-94
Microsoft EmployeeHi sholy29,
from a quick look to the telemetry for the Request ID you shared, I see that some of your queries with staging enabled got a problem which seems linked to a Microsoft Entra ID token: if the error persists, please raise a support ticket.
Worth mentioning that, given your dataflow is writing to destinations, I assume that you do not need to stage such queries: if that's the case, you can try to uncheck the "Enable staging" option (see picture below) for all of them and re-run the dataflow by clicking "Save & run"
Best regards,
Alessandro
Hi Alessandro,
Thank you for your quick response, that solved the problem. Thank you very much!
Does that mean I can't use the function at all, even though it should offer advantages? Or do I have to make special settings for it? Can you help me with that?
- Alven
Hi CRadziwill ,
usage (or not) of staging should not cause any failure, and if you instead get one, it usually means there is a problem somewhere thay requires an investigation / support ticket.
In general, staging can help with performance in some cases, but it really depends on the scenario.
For example, if your query does not perform complex transformations and is simply copying data from a SQL database to a Lakehouse using an output destination, staging is not needed, and it's actually disabled automatically when setting the output destination.
Some useful information can be found in Best practices for getting the best performance with Dataflow Gen2 in Fabric Data Factory - Microsoft Fabric | Microsoft Learn.
Regards,
Alessandro