My DataFlow Gen 2 Fails with Unknown Evaluation Error 999999 (Request ID: fcd89914-0dd9-44ea-9b09-94

[sholy29]

I do not understand why the Dataflow gen 2 is too buggy. This should be a revolutionary product from Fabric but it just cannot work without errors all the time.

I have a dataflow gen 2 that takes data from a lakehouse and transforms it and saves it in a destination. It has been working very fine for some few days, now it does not work baut instead shows this error. Error Details: We encountered an error during evaluation. Details: Unknown evaluation error code: 999999 (Request ID: fcd89914-0dd9-44ea-9b09-940f84fa6e3e).

The erroe message is very vague. Yes, I have access to the undelying data. The lakehouse it connects to has shortcuts from mirroring SQL Server. I do have access to this shortcut lakehouse data.

Can any one help me with this ?

[Alven]

Hi @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

[sholy29]

Thanks Alessandro.

I do have many queries that are not writing to a destination. I need those queries because I need to merge (join) them (denormalise) with other queries to have the final ouput table that then writes to a destination. I noticed that it is those queries without a destination that has staging enabled by default. 

Could this be the cause of the problem? Should I disable staging for the queries without destination?

Thank you

[v-prasare]

Hi @sholy29 ,
Thanks for reaching MS Fabric community support

In this case please consider raising a support ticket for further assistance. To raise a support ticket with request Id and other details for Fabric and Power BI, kindly follow the steps outlined in the following guide:

How to create a Fabric and Power BI Support ticket - Power BI | Microsoft Learn

Thanks,

Prashanth Are