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Troubleshooting User-Dependent Authorization in Identity-Aware Production Views

Understanding the Problem

I was tasked with investigating why certain users were unable to access the secure_customers view in the production.secure schema, even though the view was supposed to grant access based on their identity. The view was designed to be identity-aware, meaning it should allow access only to users who met specific criteria. But some users were being denied access, while others were not. I needed to understand why this was happening and how to fix it.

Starting with the Basics

I began by checking the structure of the secure_customers view to understand how it was defined. I ran the SHOW CREATE TABLE command to see the exact DDL of the view.

SHOW CREATE TABLE production.secure.secure_customers;

The output showed that the view was built on a base table and included a WHERE clause that referenced the current user. This suggested that the view was designed to filter rows based on the user’s identity, which is a common pattern in identity-aware views.

Checking Access Permissions

Next, I wanted to verify what permissions were granted on the view itself. I ran the SHOW GRANTS command to see which users or roles had access to the view.

SHOW GRANTS ON VIEW production.secure.secure_customers;

The result showed that the view was accessible to a specific role, secure_user_role, which was supposed to be assigned to users who needed access. However, I noticed that some users who should have been part of that role were not able to access the view, while others were.

Validating the Current User

To understand why some users were being denied access, I ran the SELECT current_user() command to see what user was currently logged in.

SELECT current_user();

This helped confirm that the user I was logged in as was indeed part of the secure_user_role and should have access. But I still couldn’t explain why some other users, who were also part of the same role, were being denied access.

Testing Access with the View

To get a clearer picture, I decided to actually query the view and see what was happening. I ran a SELECT statement to retrieve some data from the secure_customers view.

SELECT * FROM production.secure.secure_customers;

The query returned data, confirming that the view was working correctly for the current user. But when I tried the same query with a different user who should have had access, I received an error: Permission denied. This was a clear indication that the view’s access control was not behaving as expected.

Diagnosing the Issue

I realized that the view’s WHERE clause might be filtering out rows based on the user’s identity, but the actual access control was being enforced by the Unity Catalog’s access policies. Since the view was defined with a WHERE clause that referenced the user, it was effectively restricting access to only those users who met the condition in that clause.

But the problem wasn’t with the view itself—it was with how the access policies were applied. Some users who should have had access were not being recognized by the system, which could be due to misconfiguration in the role assignments or missing grants.

Resolving the Issue

I went back to the SHOW GRANTS output to double-check the permissions. I noticed that some users were not assigned to the secure_user_role, even though they should have been. I corrected this by granting the role to those users and verified that access was restored for them.

I also checked the WHERE clause of the view to ensure it was correctly referencing the current user. It was, so the issue was not with the logic of the view itself, but with the access control configuration.

Learning from the Experience

Through this process, I learned that identity-aware views in Unity Catalog are powerful but require careful configuration. The WHERE clause can be used to filter data based on the user’s identity, but it’s essential to ensure that access is also properly granted through roles and permissions.

By combining the SHOW CREATE TABLE, SHOW GRANTS, and SELECT current_user() commands, I was able to diagnose and resolve the issue. This experience reinforced the importance of understanding both the structure of views and the access control mechanisms in Unity Catalog.