SQL>  create table test tablespace users pctfree 99 as select * from dba_objects order by object_id;

Table created.

SQL> create index objd on test(object_id);

Index created.

SQL> select max(object_id) from test;     

MAX(OBJECT_ID)

--------------

         52519

session 1 首先全表更新

update test set object_id=object_id+1;

session2 随后更新

SQL> update test set object_id=52519+1 where object_id=52519;

1 row updated.

SQL> select sid,

       event,

  2    3         row_wait_obj#,

  4         row_wait_file#,

  5         row_wait_block#,

  6         row_wait_row#

  7    from v$session

  8   where event = 'enq: TX - row lock contention'

  9  /

       SID EVENT                                                            ROW_WAIT_OBJ# ROW_WAIT_FILE# ROW_WAIT_BLOCK# ROW_WAIT_ROW#

---------- ---------------------------------------------------------------- ------------- -------------- --------------- -------------

       146 enq: TX - row lock contention                                            52518              4           50375             0

session 1 被session 2 阻塞 ， 造成争用的行是 4号文件 50375  块的 第0行

构造出rowid 

SQL> select dbms_rowid.ROWID_CREATE(1,52518,4,50375,0) from dual;

DBMS_ROWID.ROWID_C

------------------

AAAM0mAAEAAAMTHAAA

SQL> select object_id from test where rowid='AAAM0mAAEAAAMTHAAA';

OBJECT_ID

----------

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