This closes a session explicitly, disconnecting from the DBMS server. It takes effect immediately. Any uncommitted transactional updates are rolled back. Some resources associated with the session are also freed.
Cursors for this session are not closed by the closing of the session, but they will no longer be able to access the database, but will still use some resources. It is recommended that cursors be closed before closing the session. All resources associated with a session are only freed when both the session and all the cursors are closed.