Oracle 数据泵 content=data_only

下面看一个试验 ,验证的是只导出数据后，可以恢复，就算是表结构已经变化了，他也能把相应的列恢复，1）SQL> desc liuwenhe.liuwenhe; Name Null？ Type ----------------------------------------- -------- ---------------------------- X NOT NULL NUMBER（38） Y NUMBER（38）
2）SQL> select * from liuwenhe.liuwenhe; X Y---------- ---------- 1
3
3
3
2
4
4
5
5
8
6
9

6 rows selected.
3）[Oracle@rac1 expdp]$ expdp system/manager123 directory=bak dumpfile=hhhf.dmp tables=liuwenhe.liuwenhe;Export: Release 11.2.0.3.0 - Production on Mon Jul 6 11:52:56 2015Copyright （c） 1982, 2011, Oracle and/or its affiliates. All rights reserved.Connected to: Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production
With the Partitioning, Real Application Clusters, OLAP, Data Mining
and Real Application Testing options
Starting "SYSTEM"."SYS_EXPORT_TABLE_03": system/******** directory=bak dumpfile=hhhf.dmp tables=liuwenhe.liuwenhe
Estimate in progress using BLOCKS method...
Processing object type TABLE_EXPORT/TABLE/TABLE_DATA
Total estimation using BLOCKS method: 64 KB
Processing object type TABLE_EXPORT/TABLE/TABLE
Processing object type TABLE_EXPORT/TABLE/INDEX/INDEX
Processing object type TABLE_EXPORT/TABLE/CONSTRAINT/CONSTRAINT
Processing object type TABLE_EXPORT/TABLE/INDEX/STATISTICS/INDEX_STATISTICS
Processing object type TABLE_EXPORT/TABLE/STATISTICS/TABLE_STATISTICS
. . exported "LIUWENHE"."LIUWENHE" 5.492 KB 6 rows
Master table "SYSTEM"."SYS_EXPORT_TABLE_03" successfully loaded/unloaded
******************************************************************************
Dump file set for SYSTEM.SYS_EXPORT_TABLE_03 is:
/backup/expdp/hhhf.dmp
Job "SYSTEM"."SYS_EXPORT_TABLE_03" successfully completed at 11:53:10
4）SQL> alter table liuwenhe.liuwenhe drop column y;

Table altered.
5）SQL> truncate table liuwenhe.liuwenhe;

Table truncated.
6）[oracle@rac1 expdp]$ impdp system/manager123 directory=bak dumpfile=hhhf.dmp tables=liuwenhe.liuwenhe content=data_only;

Import: Release 11.2.0.3.0 - Production on Mon Jul 6 11:55:07 2015Copyright （c） 1982, 2011, Oracle and/or its affiliates. All rights reserved.Connected to: Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit ProductionWith the Partitioning, Real Application Clusters, OLAP, Data Miningand Real Application Testing optionsMaster table "SYSTEM"."SYS_IMPORT_TABLE_04" successfully loaded/unloadedStarting "SYSTEM"."SYS_IMPORT_TABLE_04": system/******** directory=bak dumpfile=hhhf.dmp tables=liuwenhe.liuwenhe content=data_onlyProcessing object type TABLE_EXPORT/TABLE/TABLE_DATA. . imported "LIUWENHE"."LIUWENHE" 5.492 KB 6 rowsJob "SYSTEM"."SYS_IMPORT_TABLE_04" successfully completed at 11:55:137）SQL> select * from liuwenhe.liuwenhe; X---------- 1 2 3 4 5 66 rows selected.总结：Oracle数据泵，逻辑备份和恢复工具，他直接在逻辑从面操作，不能想象成单纯的insert ，而且只导出数据，然后恢复数据时候，可以不用写remap_tablespace这个参数，tables=liuwenhe.liuwenhe 这里要是没有写前缀liuwenhe,而写成tables=liuwenhe,系统就认为是system用户下的liuwenhe表，而出错。更多Oracle相关信息见Oracle 专题页面 http://www.linuxidc.com/topicnews.aspx？tid=12本文永久更新链接地址