1. 当前运行的sql语句 

select sid, v$session.username 用户名, 

last_call_et 持续时间, 
status 状态, 
LOCKWAIT 等待锁, 
machine 用户电脑名, 
logon_time 开始登入时间, 
sql_text 
from v$session, v$process, v$sqlarea 
where paddr = addr 
and sql_hash_value = http://blog.soso.com/qz.q/hash_value 
and status = 'ACTIVE' 
and v$session.username is not null 
order by last_call_et desc; 

2.根据sid查询已经执行过的sql 

select sql_text from v$sqlarea a,v$session b where a.SQL_ID=b.PREV_SQL_ID and b.SID=&sid; 

3.根据sid查询当前执行的sql 

select sql_text from v$sqlarea where (hash_value,address)=(select sql_hash_value,sql_address from v$session where sid=&sid); 

4.查询oracle 锁表情况

select sess.sid, 

sess.serial#, 
lo.oracle_username, 
lo.os_user_name, 
ao.object_name, 
lo.locked_mode 
from v$locked_object lo, 
dba_objects ao, 
v$session sess 
where ao.object_id = lo.object_id and lo.session_id = sess.sid

5.杀掉锁表的语句 

如有记录则表示有lock，记录下SID和serial# ，将记录的ID替换下面的738,1429，即可解除LOCK 

alter system kill session '1793,25320';