Forum Discussion

Yazdan's avatar
Yazdan
Advocate II
1 year ago
Solved

Bug: Inconsistent Behavior When Using Lakehouse Tables in Warehouse-Scoped Queries in Copy Activity

Hi Fabric Team, I’m writing to report a bug we've encountered while using Microsoft Fabric. we rely on Fabric for our ETL and ELT processes, leveraging both Warehouse and Lakehouse features. As you...
Copy Activity
Data Warehouse
Lakehouse
  • Yazdan's avatar
    Yazdan
    1 year ago

    Hi,

    Thank you for your suggestion.

    I have already raised a support ticket with Microsoft — Service Request #: 2505130030000051 — and I’m currently waiting for their response.

    I’ll share any updates or resolutions here once I hear back.

    Best regards,
    Yazdan Aghajanian

burakkaragoz's avatar
burakkaragoz
Super User
1 year ago

Hi Yazdan ,

 

Thanks for flagging this—this definitely sounds like a sneaky and potentially dangerous issue 😬

You're absolutely right: if a Copy Activity is scoped to Warehouse, it shouldn’t silently allow Lakehouse tables in the query. Even if it technically works in some cases, the lack of validation can lead to hard-to-detect bugs like the one you experienced.

A few thoughts:

  • Until this is addressed, it might be safer to strictly separate Lakehouse and Warehouse logic in your pipelines.
  • You could also consider adding a manual validation step in your process to catch any cross-environment references before deployment.
  • Totally agree that Fabric should implement a validation layer here—it would save a lot of headaches in production.

Appreciate you sharing this—it’ll definitely help others avoid the same trap.

If my response resolved your query, kindly mark it as the Accepted Solution to assist others. Additionally, I would be grateful for a 'Kudos' if you found my response helpful.

Yazdan's avatar
Yazdan
Advocate II
1 year ago

Hi,

Yes, I had previously implemented a workaround to identify the issue, and I’ve also raised a support ticket with Microsoft — Service Request #: 2505130030000051. I'm currently waiting for their response.

I completely agree with your points—having proper validation between Warehouse and Lakehouse environments would definitely help avoid these subtle and potentially risky issues. Hopefully, this gets addressed soon.

Thanks again for your insights and support!

Best regards,
Yazdan Aghajanian