平常都是对数据库或schema备份还原的，对特定table导入的事情倒是做得很少！
今天要导入指定table操作时，发现oracle有些个别约束！
不多说了，看示例吧！
错误一：不能同时使用schemas与tables参数
$ impdp hfy121123/kingdee schemas=hfy tables=CT_HSE_CusBaseCode remap_schema=hfy:HFY121123 directory=easbak dumpfile=hfy201211230200.dmp logfile=20121123imp.log Import: Release 11.2.0.2.0 - Production on Fri Nov 23 16:03:01 2012 Copyright (c) 1982, 2009, Oracle and/or its affiliates. All rights reserved. Connected to: Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production With the Partitioning, OLAP, Data Mining and Real Application Testing options UDI-00010: multiple job modes requested, schema and tables. $
错误二：CT_HSE_CusBaseCode默认被认为是当前用户的表，所以在导入时需要限定
$ impdp hfy121123/kingdee tables=CT_HSE_CusBaseCode remap_schema=hfy:HFY121123 directory=easbak dumpfile=hfy201211230200.dmp logfile=20121123imp.log Import: Release 11.2.0.2.0 - Production on Fri Nov 23 15:38:47 2012 Copyright (c) 1982, 2009, Oracle and/or its affiliates. All rights reserved. Connected to: Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production With the Partitioning, OLAP, Data Mining and Real Application Testing options ORA-39002: invalid operation ORA-39166: Object HFY121123.CT_HSE_CUSBASECODE was not found. $
错误三：其实严格来说这个算不得错误的，起码在语法上并没有什么问题。
$ impdp hfy121123/kingdee tables=hfy.CT_HSE_CusBaseCode directory=easbak dumpfile=hfy201211230200.dmp logfile=20121123imp.log Import: Release 11.2.0.2.0 - Production on Fri Nov 23 16:12:28 2012 Copyright (c) 1982, 2009, Oracle and/or its affiliates. All rights reserved. Connected to: Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production With the Partitioning, OLAP, Data Mining and Real Application Testing options Master table "HFY121123"."SYS_IMPORT_TABLE_01" successfully loaded/unloaded Starting "HFY121123"."SYS_IMPORT_TABLE_01": hfy121123/******** tables=hfy.CT_HSE_CusBaseCode directory=easbak dumpfile=hfy201211230200.dmp logfile=20121123imp.log Processing object type SCHEMA_EXPORT/TABLE/TABLE ORA-39151: Table "HFY"."CT_HSE_CUSBASECODE" exists. All dependent metadata and data will be skipped due to table_exists_action of skip Processing object type SCHEMA_EXPORT/TABLE/TABLE_DATA Processing object type SCHEMA_EXPORT/TABLE/INDEX/INDEX Processing object type SCHEMA_EXPORT/TABLE/CONSTRAINT/CONSTRAINT Processing object type SCHEMA_EXPORT/TABLE/INDEX/STATISTICS/INDEX_STATISTICS Processing object type SCHEMA_EXPORT/TABLE/STATISTICS/TABLE_STATISTICS Job "HFY121123"."SYS_IMPORT_TABLE_01" completed with 1 error(s) at 16:12:35 $
在分析这个问题前，我们先来了解下oracle关于导入导出的一个事实：oracle从数据库导出dmp文件，默认不会改变各对象（如：table、index等）的相关属性（如：schema、tablespace等）。
注：其实我也是后来才明白这个事实的，不过对于oracle在导出dmp文件时能否修改对象（如：table、index等）的属性暂时还不清楚，以后再研究吧。
既然我们已经清楚了这个情况，那出现这个问题也就能理解了：我的用户hfy121123与hfy是在相同数据库实例环境下的操作，所以默认导入的表CT_HSE_CusBaseCode自然所属用户是hfy，所以也就出现表已存在的问题了！
正确：指定了表的所属用户，指定schema从hfy到hfy121123
（如果这是在不同的数据库操作，就要考虑下当前操作的数据库实例下 是否具有原导出表所属表空间 的相同的表空间名的表空间了！这，，，好别扭啊，不知道该如何描述才能表达我的意思~``~）
$ impdp hfy121123/kingdee tables=hfy.CT_HSE_CusBaseCode remap_schema=hfy:HFY121123 directory=easbak dumpfile=hfy201211230200.dmp logfile=20121123imp.log Import: Release 11.2.0.2.0 - Production on Fri Nov 23 14:10:38 2012 Copyright (c) 1982, 2009, Oracle and/or its affiliates. All rights reserved. Connected to: Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production With the Partitioning, OLAP, Data Mining and Real Application Testing options Master table "HFY121123"."SYS_IMPORT_TABLE_01" successfully loaded/unloaded Starting "HFY121123"."SYS_IMPORT_TABLE_01": hfy121123/******** tables=hfy.CT_HSE_CusBaseCode remap_schema=hfy:HFY121123 directory=easbak dumpfile=hfy201211230200.dmp logfile=20121123imp.log Processing object type SCHEMA_EXPORT/TABLE/TABLE Processing object type SCHEMA_EXPORT/TABLE/TABLE_DATA . . imported "HFY121123"."CT_HSE_CUSBASECODE" 688.5 KB 2471 rows Processing object type SCHEMA_EXPORT/TABLE/INDEX/INDEX Processing object type SCHEMA_EXPORT/TABLE/CONSTRAINT/CONSTRAINT Processing object type SCHEMA_EXPORT/TABLE/INDEX/STATISTICS/INDEX_STATISTICS Processing object type SCHEMA_EXPORT/TABLE/STATISTICS/TABLE_STATISTICS Job "HFY121123"."SYS_IMPORT_TABLE_01" successfully completed at 14:10:47 $
这里顺便再提下另外的问题：当然如果我不指定remap_tablespace参数，表导入后的所属表空间也是不会发生变化的，如果当前数据库不存在相应的表空间就会报错了）。
其实，这些都是可举一反三的！
稍稍理解下oracle的想法，理解下这几个参数的含义，其它的备份还原操作自然也就明白知道该怎么使用了！！