ORA-01940 cannot drop a user that is currently connected

问题：Oracle 数据库删除用户提示“ORA-01940 cannot drop a user that is currently connected”

解决办法：

1. 仔细检查以确保用户未连接到当前实例

   select s.sid, s.serial#, s.status, p.spid
   from v$session s, v$process p
   where s.username = 'myuser'
   and p.addr (+) = s.paddr;
   

   如果有连接的用户，执行下面语句，然后再次查询确认，如果已经显示连接都被 kill，重 新执行删除用户语句

   alter system kill session '<sid>,<serial#>';
   

2. 如果还是不行，检查用户是否未与任何活动作业关联

   select job from dba_jobs where log_user='myuser';
   

3. 最后，检查用户是否未与任何Streams复制队列关联

   select queue_table, qid from dba_queues where owner='myuser';
   
   select apply_name from dba_apply where queue_owner='myuser'; 
   
   select capture_name, queue_name from dba_capture where
   queue_owner='myuser';
   
   select propagation_name from dba_propagation where source_queue_owner='myuser' or
   destination_queue_owner='myuser';