Forum Discussion
Fabric SQL database column name changes randomly
Hi naveen_das ,
This issue is something several people have noticed when using Direct Lake and mirrored tables in Fabric. When mirroring is enabled, especially with auto-generated schemas, column names can sometimes shift because of metadata syncs or schema inference on the OneLake side.
This generally happens if:
- The source table's schema or metadata changes, even slightly (like case sensitivity or data type).
- The mirroring process re-checks schema during a refresh or sync.
- The mirrored table is recreated or rehydrated behind the scenes.
Here's what you can try for better stability:
- Define explicit column naming and indexes in your original SQL tables, rather than relying on auto-generated ones.
- In your semantic model, map columns explicitly instead of using auto-detection.
- Try to avoid renaming or altering columns in the source system after mirroring is set up.
- If stability is critical, use Lakehouse tables with defined schemas instead of mirrored ones.
Lastly, keep an eye out for any known bugs or updates from Microsoft regarding this behavior. It might be something under review or with a hotfix pending.
If this helped, feel free to mark as Accepted Solution so others can find the answer easily!
Hi naveen_das ,
Yeah, this has been observed by a few folks working with Direct Lake and mirrored tables in Fabric. When using mirroring, especially with auto-generated schemas, column names can sometimes shift due to metadata sync issues or schema inference updates on the OneLake side.
This usually happens when:
- The source system changes column metadata (even minor ones like casing or type hints)
- The mirroring process re-evaluates schema during refresh or sync
- The table is recreated or rehydrated behind the scenes
What you can try:
- Use explicit column mapping in your semantic model instead of relying on auto-detection
- Avoid renaming or altering columns in the source system once mirroring is active
- If possible, use Lakehouse tables with defined schemas instead of mirrored ones for more stability
Also, worth checking if there’s an open issue or update from Microsoft on this — it might be a known behavior under review.
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.