Question: I see that there is a new
disable_archive_logging parameter for Data
Pump 12c.
Answer:
One nice Oracle12c feature is the ability to run in nologging mode, disabling archive logging during a large import. In this example we suppress the use of redo logs during the import:
impdp scott/tiger parfile=mypar.par transform=disable_archive_logging:y
In this example, we only suppress the redo generation for indexes during the import. In this case, an abort would require manual rebuilding of the indexes.
impdp scott/tiger parfile=mypar.par transform=disable_archive_logging:y:index
Note: When running with transform=disable_archive_logging, an abort will not roll-back and you will need to restore the table. Hence, always take a backup of the target table before using the transform=disable_archive_logging option.
Oracle experts have noted that using the disable_archive_logging option results in a measurable improvement in import load times, making this an important performance tip.
Also note that disable_archive_logging will have no effect if the database is running in force logging mode.
Oracle offers
disable_archive_logging in Data Pump
to simply disable the writing on archived redo logs, and
thereby speeding-up export operations. You can set
disable_archive_logging at several levels, globally and for
specific tables and indexes:
- transform=disable_archive_logging:Y
- transform=disable_archive_logging:Y:tablename
- transform=disable_archive_logging:Y:indexname
Here is a
sample invocation of Data Pump, a schema import that
disables arching logging:
/u01/app/oracle>
impdp dumpfile=pythian.dmp table_exists_action=append
schemas=scott transform=disable_archive_logging:Y
In most cases you would want to run the disable
archive logging parameter at the schemas level.
|
|
 |
|
Get the Complete
Oracle Utility Information
The landmark book
"Advanced Oracle
Utilities The Definitive Reference" contains over 600 pages of
filled with valuable information on Oracle's secret utilities.
This book includes scripts and tools to hypercharge Oracle 11g
performance and you can
buy it
for 30% off directly from the publisher.
|
|
|
| |
|
Burleson is the American Team
Note:
This Oracle
documentation was created as a support and Oracle training reference for use by our
DBA performance tuning consulting professionals.
Feel free to ask questions on our
Oracle forum.
Verify
experience!
Anyone
considering using the services of an Oracle support expert should
independently investigate their credentials and experience, and not rely on
advertisements and self-proclaimed expertise. All legitimate Oracle experts
publish
their Oracle
qualifications.
Errata?
Oracle technology is changing and we
strive to update our BC Oracle support information. If you find an error
or have a suggestion for improving our content, we would appreciate your
feedback. Just
e-mail:
 and include the URL for the page.
Copyright © 1996 - 2020
All rights reserved by
Burleson
Oracle ®
is the registered trademark of Oracle Corporation.
|
|
