Cross-Database Queries Don't Work As Documented

[KyleChamberlin]

The Microsoft documents at these two links both indicate that cross-database queries should be supported by the Fabric SQL Database Preview, through 3-part identifiers. However when I try this in practice, I get an error message, both when opening the database directly and querying there, and also when trying it through the SQL Analytics Endpoint as suggested in the 2nd link.

SQL database Overview (Preview) - Microsoft Fabric | Microsoft Learn
Features comparison: Azure SQL Database and SQL database (preview) - Microsoft Fabric | Microsoft Le...

The errors I get from each query access method are:

"Reference to database and/or server name in X is not supported in this version of SQL Server"
"Invalid object name X"

Is there some configuration that needs to be set, or is this feature not available in all Fabric regions? I know cross-database queries have not been supported in the past, but these documents indicate that it should be supported at present.

[Adityakumar]

Cross-database queries in Microsoft Fabric SQL Database only work via the SQL Analytics Endpoint and within the same workspace, using three-part names (e.g., Database.Schema.Table). They do not work when connecting directly to an individual SQL database, which causes the errors you see. No special configuration or regional setting is required make sure you're querying from the SQL Analytics Endpoint, and all referenced databases/warehouses are in the same workspace.

[idrismotiwala]

Hi @KyleChamberlin , @NandanHegde  is correct, you can use the SQL Analytics endpoint to cross-query the 2 databases as an option. SQL Analytics endpoint reflect the replicated/mirrored data from SQL operational/transactional data in OneLake which is stored in delta-parquet format and is read-only. We have received feedback and is in our backlog to assess and evaluate cross-database query using SQL operational endpoint that points to the underlying transactional database from the Fabric database query editor

[NandanHegde]

Cross Database queries do work but only between SQL analytics end point only.

DB1 :

DB 2 :

So cross DB queries does work between SQL DB SQL analytics end point

[v-kpoloju-msft]

Hi @KyleChamberlin,

Thank you for raising this question and providing the helpful documentation references.

You are correct that both the Fabric SQL Database (Preview) overview and the feature comparison articles indicate support for cross-database queries using 3-part identifiers.

However, based on current behaviour and internal updates, this functionality is not yet fully supported in the current Fabric SQL database engine, despite what the documentation implies. The error messages you are receiving:

• Reference to database and/or server name in X is not supported in this version of SQL Server
• Invalid object name X

are consistent with limitations seen when attempting unsupported cross-database references.

Workaround (If applicable): If cross-database data access is required, you can consider:

• Duplicating required tables in the current database.
• Or using Lakehouse’s with Direct Lake mode to query across datasets within the same workspace context.

We suggest submitting this as feedback directly on the documentation page or through the Microsoft Fabric Ideas portal, so the team can clarify documentation or update roadmap support for this feature: Microsoft Fabric Ideas

Hope this helps clarify things and let me know what you find after giving these steps a try happy to help you investigate this further.

Thank you for using the Microsoft Community Forum.

[v-kpoloju-msft]

Hi @KyleChamberlin,

Just checking in to see if the issue has been resolved on your end. If the earlier suggestions helped, that’s great to hear! And if you’re still facing challenges, feel free to share more details happy to assist further.

Thank you!