Check whether there is an sql for the lock table in Oracle

1. Check whether there is an sql for the lock table

 
select 'blocker('||lb.sid||':'||sb.username||')-sql:'|| qb.sql_text blockers, 
'waiter ('||lw.sid||':'||sw.username||')-sql:'|| qw.sql_text waiters 
from v$lock lb, 
v$lock lw, 
v$session sb, 
v$session sw, 
v$sql qb, 
v$sql qw 
where lb.sid=sb.sid 
and lw.sid=sw.sid 
and sb.prev_sql_addr=qb.address 
and sw.sql_address=qw.address 
and lb.id1=lw.id1 
and sw.lockwait is not null 
and sb.lockwait is null 
and lb.block=1 ; 

2. View locked tables

 
select p.spid,a.serial#,c.object_name,b.session_id,b.oracle_username,b.os_user_name 
from v$process p,v$session a, v$locked_object b,all_objects c 
where p.addr=a.paddr and a.process=b.process and c.object_id=b.object_id ; 

3. Check which user and which process caused deadlock and the level of lock

 
select b.owner,b.object_name,l.session_id,l.locked_mode fromv$locked_object l, dba_objects 

4. View the connected process

 
SELECT sid, serial#, username, osuser FROMv$session; 

5. See which session caused it

 
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; 

6. Kill the process

 
alter system kill session 'sid,serial#'; 

sid is the sid and serid found in Step 5