Before you upgrade, check for and stop any current database sessions.
If WebLogic Server is running, stop it. See Oracle® Fusion
Middleware Administering Server Startup and Shutdown for Oracle WebLogic
Server (12.2.1.3) at https://docs.oracle.com/middleware/12213/wls/START/.
Log files for the AdminServer and the DMWServer are located
in:
SELECT 'USER: '||s.username||' SID: '||s.sid||' SERIAL #: '||S.SERIAL# "USER
HOLDING LOCK", s.inst_id
FROM gv$lock l
,dba_objects o
,gv$session s
WHERE l.id1 = o.object_id
AND s.sid = l.sid
AND o.owner = 'CDR'
AND o.object_name = 'DME_DISC_WORKTABLIST';
This query returns the user, SID, serial number, and instance ID of each
current session.
Disconnect each current session, passing in the SID and serial number:
alter system disconnect session 'SID, serial_number' IMMEDIATE