1.查看是否有被鎖的表：

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

2.查看是哪個進程鎖的

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

3.殺掉進程

alter system kill session 'sid,serial#';