一、查询出死锁的SID等信息
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#;

二、根据SID定位阻塞语句
SELECT /+ PUSH_SUBQ /
Command_Type,sql_Text,Sharable_Mem,Persistent_Mem,Runtime_Mem,Sorts,Version_Count,Loaded_Versions,Open_Versions,Users_opening,Executions,Users_Executing,Loads,First_Load_Time,Invalidations,Parse_Calls,Disk_Reads,Buffer_Gets,Rows_Processed,SYSDATE Start_Time,
SYSDATE Finish_Time,‘>‘ || Address sql_Address,‘N‘ Status
FROM V$sqlarea
WHERE Address = (SELECT sql_Address FROM V$session WHERE Sid = ？ );

三、杀死锁
--杀死锁（数据库层次--适合不太紧急场合）
select ‘alter system kill session ‘||chr(39)||t2.sid||‘,‘||t2.serial#||chr(39)||‘immediate;‘
from v$locked_object t1,v$session t2
where t1.session_id=t2.sid order by t2.logon_time

--杀死锁（操作系统层次--适合紧急场合）
select ‘kill -9 ‘||t3.spid
from v$locked_object t1,v$session t2,v$process t3
where t1.session_id=t2.sid And t2.paddr = t3.addr order by t2.logon_time

附日常会话查询语句：
--所有会话信息
Select From v$sessionSelect Count() From v$session--会话关键信息Select USERNAME,status,state,MACHINE,logon_time From V$SESSION Order By username,MACHINE