Learn the purpose and how to get to the bottom of the ORA-01042 error message in Oracle.
When you stumble upon an ORA-01042 error, the following error message will appear:
ORA-01042: detaching a session with open cursors not allowed
You tried to detach from an Oracle session whilst there was an open cursor.
The option(s) to resolve this Oracle error are:
Close all cursors and then retry detaching the session.