Given a Performance Schema thread ID, returns the account associated with the thread.user_name@host_name
in_thread_id BIGINT UNSIGNED: The thread ID for which to return the account. The value should match the THREAD_ID column from some Performance Schema threads table row.
mysql> SELECT sys.ps_thread_account(sys.ps_thread_id(CONNECTION_ID()));
+----------------------------------------------------------+
| sys.ps_thread_account(sys.ps_thread_id(CONNECTION_ID())) |
+----------------------------------------------------------+
| root@localhost |
+----------------------------------------------------------+