expdp report error when export tables

;;;
Export: Release 10.2.0.1.0 - 64bit Production on Friday, 09 February, 2007 11:02:01

Copyright (c) 2003, 2005, Oracle.  All rights reserved.
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Connected to: Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - 64bit Production
With the Partitioning, OLAP and Data Mining options
Starting "BOSS"."SYS_EXPORT_TABLE_03":  parfile=exp.par
Estimate in progress using BLOCKS method...
Processing object type TABLE_EXPORT/TABLE/TABLE_DATA
ORA-39125: Worker unexpected fatal error in KUPW$WORKER.GET_TABLE_DATA_OBJECTS while calling DBMS_METADATA.FETCH_XML_CLOB []
ORA-04031: unable to allocate 64 bytes of shared memory ("shared pool","SELECT /*+rule*/ SYS_XMLGEN(...","sql area","qeeRwo: qeeCreateRwo")
ORA-06512: at "SYS.DBMS_SYS_ERROR", line 95
ORA-06512: at "SYS.KUPW$WORKER", line 6235
----- PL/SQL Call Stack -----
  object      line  object
  handle    number  name
0x1f40d1d78     14916  package body SYS.KUPW$WORKER
0x1f40d1d78      6300  package body SYS.KUPW$WORKER
0x1f40d1d78      9120  package body SYS.KUPW$WORKER
0x1f40d1d78      3873  package body SYS.KUPW$WORKER
0x1f40d1d78      6917  package body SYS.KUPW$WORKER
0x1f40d1d78      1262  package body SYS.KUPW$WORKER
0x1f4347280         2  anonymous block
Job "BOSS"."SYS_EXPORT_TABLE_03" stopped due to fatal error at 11:02:08
~

exp.par檔案如下
---------------------------------------

userid=boss/xxx
directory=dump_files1
ESTIMATE_ONLY=y
tables=(
BOSSHEALTHDATA                 ,                
BOSSSELLERBASICINFO            ,
BOSSSELLERDAILYSTAT            ,
BOSSSELLERDEALBYCLASSID        ,
BOSSSELLERDEALDETAIL           ,
BOSSSELLERGROUP                ,
BOSSSELLERGROUPRELATION        ,
BOSSSELLERLEVELCRITERION       ,
BOSSSELLEROLCOMMDETAIL         ,
BOSSSTATSDATA                  ,
T_BOSSREPORT_HISINFO           ,
T_DEAL_CATEGORY                ,
T_DEAL_EXTRA_INFO              ,
T_DEAL_INFO_4_5188STAT         ,
T_DEAL_INFO_4_STAT             ,
T_DEAL_INFO_5188DELETED_ORI    ,
T_FIRST_DEAL_INFO_4_STAT       ,
T_FIRST_TENPAY_INFO_4_STAT
)
FILESIZE=800M
LOGFILE=export_20070209_5.log

$expdp parfile=exp.par



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在將shared_pool_size由160M改為250M後，重試正常.

為什麼expdp需要呼叫的對像不存在也可以執行成功?
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SQL> desc DBMS_METADATA.FETCH_XML_CLOB
ERROR:
ORA-04043: object DBMS_METADATA.FETCH_XML_CLOB does not exist

SQL> desc KUPW$WORKER.GET_TABLE_DATA_OBJECTS
ERROR:
ORA-04043: object KUPW$WORKER.GET_TABLE_DATA_OBJECTS does not exist


當指定了ESTIMATE_ONLY=y時，不能同時指定DUMPFILE,否則報錯如下
----------------------------
ORA-39201: Dump files are not supported for estimate only jobs