OneLake Security CLS/RLS issue

Hi AditiPattnaik, 
Thank you for the detailed explanation and screenshots.

Based on your scenario, the behaviour you are seeing is expected when One Lake security (CLS/RLS) is enabled and the SQL analytics endpoint is configured to use User identity. Workspace roles such as Viewer only allow users to see metadata (like table names), but actual data access is controlled separately through One Lake security permissions.

Once CLS/RLS is applied, users must be explicitly granted Read permission at the schema, table, or folder level using Manage One Lake security. Without this Read permission, the Lakehouse UI cannot preview the data, and the SQL analytics endpoint will return errors such as SELECT permission was denied.

To resolve this, please open the Lakehouse, select the affected schema or table, and use Manage One Lake security to grant the user Read permission. After allowing a short time for permission propagation, the user should be able to preview and query the data successfully, while CLS/RLS continues to enforce the intended restrictions.

Refer these links:
1. https://learn.microsoft.com/en-us/fabric/onelake/security/data-access-control-model 
2. https://learn.microsoft.com/en-us/fabric/onelake/security/get-started-security 
3. https://learn.microsoft.com/en-us/fabric/data-engineering/workspace-roles-lakehouse 
4. https://learn.microsoft.com/en-gb/fabric/data-engineering/lakehouse-sql-analytics-endpoint 

Hope this clarifies. Let us know if you have any doubts regarding this. We will be happy to help.

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