Table Locks

To view the session which is locking the table:

SELECT o.owner, o.object_name, o.object_type, o.last_ddl_time, o.status, l.session_id, l.oracle_username, l.locked_mode
FROM dba_objects o, gv$locked_object l
WHERE o.object_id = l.object_id;

select c.owner, c.object_name, c.object_type,b.sid, b.serial#, b.status, b.osuser, b.machine 
from v$locked_object a , v$session b, dba_objects c 
where b.sid = a.session_id 
and a.object_id = c.object_id;


select 
username,
v$lock.sid,
trunc(id1/power(2,16)) rbs,
bitand(id1,to_number('ffff','xxxx'))+0 slot,
id2 seq,
lmode,
request
from v$lock, v$session
where v$lock.type = 'TX'
and v$lock.sid = v$session.sid
and v$session.username = USER
/


select
(select username || ' - ' || osuser from v$session where sid=a.sid) blocker,
a.sid || ', ' ||
(select serial# from v$session where sid=a.sid) sid_serial,
' is blocking ',
(select username || ' - ' || osuser from v$session where sid=b.sid) blockee,
b.sid || ', ' ||
(select serial# from v$session where sid=b.sid) sid_serial
from v$lock a, v$lock b
where a.block = 1
and b.request > 0
and a.id1 = b.id1
and a.id2 = b.id2;