SQL*Plus: Release 10.2.0.1.0 - Production on Ćar Eyl 26 09:46:22 2007

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-- Step A, bitmap index blocking lock, 3 sessions
--
-- FROM SESSION - 1
SQL> conn hr/hr
Connected.
SQL> create bitmap index bi_tx_sex on tx(sex) ;

Index created

SQL> select distinct sid from v$mystat ;

       SID
----------
       966

SQL> update tx set sex='FEMALE' where num=3 ;

1 row updated

-- FROM SESSION - 2
SQL> conn hr/hr
Connected.
SQL> select distinct sid from v$mystat ;

       SID
----------
       967

SQL> update tx set sex='FEMALE' where num=4 ;

..waiting

-- FROM SESSION - 3
SQL> conn / as sysdba
Connected.
SQL> set linesize 20000
SQL> @D:\oraclexe\app\oracle\product\10.2.0\server\RDBMS\ADMIN\utllockt.sql
..

WAITING_SESSION   LOCK_TYPE         MODE_REQUESTED MODE_HELD      LOCK_ID1          LOCK_ID2
----------------- ----------------- -------------- -------------- ----------------- -----------------
966               None                                                              
   967            Transaction       Share          Exclusive      393241            945
..

SQL> select sid, type, id1, id2, lmode, request, ctime from v$lock
  2  where sid in (24, 37) order by sid ;

       SID TYPE        ID1        ID2      LMODE    REQUEST      CTIME
---------- ---- ---------- ---------- ---------- ---------- ----------
       966 TM        57811          0          3          0         27
       966 TX       393241        945          6          0         27
       967 TX       524303        938          6          0         18
       967 TX       393241        945          0          4         18
       967 TM        57811          0          3          0         18
	   
-- @ SESSION - first 1 and than 2
SQL> rollback ;