ora-00054:resource busy and acquire with nowait specified解决方法

drop user gnsael cascade;
报错：
ora-00054:resource busy and acquire with nowait specified解决方法

解决方法：
查看相关的用户表是否有被锁，如果被锁，那就结束掉它
select b.owner,b.object_name,a.session_id,a.locked_mode
from v$locked_object a,dba_objects b
where b.object_id = a.object_id;

然后查看SID对应的serial_id

select b.username,b.sid,b.serial#,logon_time
from v$locked_object a,v$session b
where a.session_id = b.sid order by b.logon_time;

KILL掉：
alter system kill session 'sid,serial#';