跟踪期间咱们再次测试一下，看看有没有其他线索。

新开一个进程，找出其sid, serial和spid等信息：ora9i@cs_dc01:/ora9i > sqlplus pubuser/pubuser

SQL*Plus: Release 9.2.0.4.0 - Production on Mon Jan 10 11:36:25 2005

Copyright (c) 1982, 2002, Oracle Corporation. All rights reserved.

Connected to:
Oracle9i Enterprise Edition Release 9.2.0.4.0 - 64bit Production
With the Partitioning and Real Application Clusters options
JServer Release 9.2.0.4.0 - Production

SQL> select distinct sid from v$mystat;

SID
----------
33

SQL> select sid,serial# from v$session where sid=33;

SID SERIAL#
---------- ----------
33 6639

SQL> SELECT SPID,PID FROM V$PROCESS WHERE ADDR=(SELECT PADDR FROM V$SESSION WHERE SID=37);

SPID PID
------------ ----------
20552 26

SQL> SELECT SPID,PID FROM V$PROCESS WHERE ADDR=(SELECT PADDR FROM V$SESSION WHERE SID=30);

SPID PID
------------ ----------
22580 28

SQL> show parameter dump

NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
background_core_dump string partial
background_dump_dest string /ora9i/app/oracle/admin/csmisc
/bdump
core_dump_dest string /ora9i/app/oracle/admin/csmisc
/cdump
max_dump_file_size string UNLIMITED
shadow_core_dump string partial
user_dump_dest string /ora9i/app/oracle/admin/csmisc
/udump
SQL>

然后，再尝试对 CSNOZ629926699966 表进行操作
SQL> desc CSNOZ629926699966

。。。

还是hang住了。

于是中断这个操作（CTRL + C）：

SQL> desc CSNOZ629926699966
ERROR:
ORA-01013: user requested cancel of current operation

SQL> select tname from tab where tname='CSNOZ629926699966';

no rows selected

SQL> 查看PUBUSER用户下的这个表，居然不存在！！

进一步证实了前面的猜测，也就是说会话37阻塞了其他所有操作表CSNOZ629926699966的会话，造成了进程的hang，当然，包括上面的SID 30和SID 33的DDL语句