首先要用dba权限的用户登录

SELECT l.session_id sid,
       s.serial#,
       l.locked_mode,
       l.oracle_username,
       l.os_user_name,
       s.machine,
       s.terminal,
       o.object_name,
       s.logon_time
  FROM v$locked_object l, all_objects o, v$session s
 WHERE l.object_id = o.object_id
   AND l.session_id = s.sid
 ORDER BY sid, s.serial#;

然后kill掉系统锁定的此记录,其中SID和serial#为上一条sql查询出的第一个和第二个字段

ALTER system KILL session 'SID,serial#';

Q.E.D.