thanks @Mo! if you refer to https://docs.databricks.com/en/sql/language-manual/sql-ref-syntax-aux-describe-table.html then yes, am aware, but this will only work if I run it on the PROD_CLUSTERS, those that have the HMS configured as their own HMS. 

It will not work as a query against the MySQL HMS, as I do from the ADHOC_CLUSTER - this cluster has a different HMS, table_name is not defined there.