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This article mainly explains "what are the new features of 12C database pump". The content of the explanation is simple and clear, and it is easy to learn and understand. Please follow the editor's train of thought. Let's study and learn "what are the new features of 12C database pump"?

DISABLE_ARCHIVE_LOGGING turns off Redo log generation (disables logging imported by the Oracle data pump)

The new TRANSFORM option DISABLE_ARCHIVE_LOGGING has been introduced in Data Pump, which provides flexibility for tables and indexes to turn off Redo log generation during import. When the DISABLE_ARCHIVE_LOGGING: y value is specified for the TRANSFORM option, the Redo logs for tables and indexes are turned off throughout the import, generating only a small number of logs. This feature relieves stress when importing large tables and reduces excessive Redo generation, thus speeding up import. This property applies to both tables and indexes. Using DISABLE_ARCHIVE_LOGGING in both non-archived and archived situations reduces import time and reduces the amount of archiving. It is important to note, however, that if the database is in FORCE LOGGING mode, the DISABLE_ARCHIVE_LOGGING parameter will not be valid.

Impdp hr/hr DIRECTORY=back DUMPFILE=test.dmp SCHEMAS=hr TRANSFORM=DISABLE_ARCHIVE_LOGGING:Y-- both tables and indexes turn off log impdp hr/hr DIRECTORY=back DUMPFILE=test.dmp SCHEMAS=hr TRANSFORM=DISABLE_ARCHIVE_LOGGING:Y:TABLE-- only tables turn off log impdp hr/hr DIRECTORY=back DUMPFILE=test.dmp SCHEMAS=hr TRANSFORM=DISABLE_ARCHIVE_LOGGING:Y TRANSFORM=DISABLE_ARCHIVE_LOGGING:N:INDEXimpdp hr/hr DIRECTORY=back DUMPFILE=test.dmp SCHEMAS=hr TRANSFORM=DISABLE_ARCHIVE_LOGGING:Y TRANSFORM=DISABLE_ARCHIVE_LOGGING:Y:INDEX

The following points should be noted about this new feature:

① after the import is complete, the state of the table and index (including the LOGGING state and whether the index is valid) will be restored to the state before the import.

After ② imports the data file with this parameter, if the corresponding datafile is restored and recovered, then the next query involving the target table will report a bad block error of ORA-01578 and ORA-26040.

Therefore, after importing the data file using this parameter, you need to make an RMAN backup of the relevant data file immediately.

12c expdp VIEWS_AS_TABLES option to export the view to a table

Use the VIEWS_AS_TABLES option to have the data pump convert the view to a table and then export. It is important to note that after exporting to the dmp file, the definition of the view has been automatically converted to the definition of the table. After the import operation is performed, it exists as a table.

Expdp system/oracle DIRECTORY=back DUMPFILE=expdp.dmp LOGFILE=expdp.log VIEWS_AS_TABLES=hr.test_viewimpdp system/oracle DIRECTORY=back DUMPFILE=expdp.dmp LOGFILE=impdp.log remap_schema=hr:sh thank you for your reading, the above is the content of "what are the new features of 12C database pump". After the study of this article, I believe you have a deeper understanding of what the new features of 12C database pump are, and the specific use needs to be verified in practice. Here is, the editor will push for you more related knowledge points of the article, welcome to follow!

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