Greetings!
When using Azure Flexible Server, you might encounter issues accessing or modifying default columns in system catalog tables such as pg_type, pg_enum, and pg_namespace. This limitation arises because Azure Flexible Server does not provide superuser access to customers, which is required to modify these tables.
To address this, it is important to understand that these system catalog tables are integral to the database's structure and are protected to maintain the integrity and stability of the database. Therefore, modifications to these tables are not permitted to avoid potential risks.
For managing and working with these tables, consider using alternative approaches that do not require direct modifications. You can achieve most administrative tasks using available PostgreSQL functions and tools provided by Azure Flexible Server.
Hope this helps. If you have any follow-up questions, please let me know. I would be happy to help.
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Regards
Geetha