Here’s a list of 30 common error codes and their descriptions related to Databricks Unity Catalog:

Authentication & Authorization Errors

1. UC1001 – Access Denied
   Description: The user does not have permission to access the catalog, schema, or table.
2. UC1002 – Invalid Credentials
   Description: Authentication failure for accessing Unity Catalog resources.
3. UC1003 – Role Not Assigned
   Description: User role is not assigned to perform the requested operation.
4. UC1004 – Invalid Token
   Description: The provided token for accessing Unity Catalog is invalid or expired.
5. UC1005 – Not Authorized for Action
   Description: User lacks permissions to execute specific Unity Catalog SQL commands.

Metastore Errors

6. UC2001 – Metastore Not Found
   Description: No metastore is configured for the current workspace.
7. UC2002 – Metastore Already Exists
   Description: Attempt to create a metastore that already exists.
8. UC2003 – Metastore Assignment Failed
   Description: Failed to assign the metastore to the workspace.
9. UC2004 – Unsupported Metastore Operation
   Description: Operation not supported for the specified metastore type.
10. UC2005 – Metastore Version Mismatch
    Description: The metastore version is incompatible with the current Unity Catalog version.

Catalog & Schema Errors

11. UC3001 – Catalog Not Found
    Description: The specified catalog does not exist.
12. UC3002 – Schema Not Found
    Description: The specified schema does not exist within the catalog.
13. UC3003 – Catalog Already Exists
    Description: Attempt to create a catalog that already exists.
14. UC3004 – Schema Already Exists
    Description: Attempt to create a schema that already exists.
15. UC3005 – Invalid Catalog or Schema Name
    Description: The catalog or schema name contains invalid characters or formatting.

Table & Data Errors

16. UC4001 – Table Not Found
    Description: The specified table does not exist.
17. UC4002 – Table Already Exists
    Description: Attempt to create a table that already exists.
18. UC4003 – Table Version Mismatch
    Description: The table version is incompatible with the requested operation.
19. UC4004 – Unsupported Data Type
    Description: The specified data type is not supported by Unity Catalog.
20. UC4005 – Missing Table Metadata
    Description: Table metadata is incomplete or corrupted.

Resource Limit & Configuration Errors

21. UC5001 – Resource Limit Exceeded
    Description: The resource limit for Unity Catalog has been exceeded.
22. UC5002 – Invalid Configuration
    Description: Configuration parameters for Unity Catalog are invalid or missing.
23. UC5003 – Cluster Not Configured for Unity Catalog
    Description: The cluster is not enabled for Unity Catalog operations.
24. UC5004 – Concurrent Modification Detected
    Description: Multiple concurrent modifications caused a conflict.
25. UC5005 – Unsupported Cluster Version
    Description: The cluster version does not support Unity Catalog features.

Networking & Connectivity Errors

26. UC6001 – Network Timeout
    Description: Network timeout while accessing Unity Catalog services.
27. UC6002 – DNS Resolution Failed
    Description: Failed to resolve the Unity Catalog service endpoint.
28. UC6003 – Connection Refused
    Description: The Unity Catalog service refused the connection request.
29. UC6004 – API Rate Limit Exceeded
    Description: Too many requests sent to Unity Catalog API, triggering rate limiting.
30. UC6005 – External Storage Access Denied
    Description: Unity Catalog could not access external storage (e.g., S3, ADLS).

How to Use and Handle These Error Codes

• Check Logs: Unity Catalog logs provide detailed information for each error code.
• Use SQL Commands: SHOW CATALOGS, SHOW TABLES, and DESCRIBE METASTORES to diagnose catalog and table-related errors.
• Review Permissions: Ensure users have the correct roles and permissions for Unity Catalog objects.
• Check Network and Cluster Configuration: Ensure clusters are Unity Catalog-enabled and network configurations allow access.