RAC 11gR2; Guaranteed Restore Points with Flashback Logging Disabled

Restore Points and Guaranteed Restore Points:

Before using flashback database solution to revert any changes made on the database, you can give a name to the SCN or specific Time until which you want to restore. This name you give is called a restore point.
A normal restore point enables you to flash the database back to a restore point within the time period determined by the DB_FLASHBACK_RETENTION_TARGET initialization parameter. A guaranteed restore point enables you to flash the database back deterministically to the restore point regardless of the DB_FLASHBACK_RETENTION_TARGET initialization parameter setting. The guaranteed ability to flash back depends on sufficient space being available in the flash recovery area.
Both normal Restore points and guaranteed restore points are stored in the control file. The main difference is that normal restore points aged out from the control file where a guaranteed restore points never age out of the control file and must be manually dropped. In normal restore point Flashback logs may be deleted in response to space pressure.

A guaranteed restore point combined with the Flashback Database command rewinds the database to its state at the restore point SCN even if the flashback database features in not enabled. If you choose to disable the flashback logging, then you cannot use the flashback database to restore the database to any point from the guaranteed restore point. However, you can flashback to the guaranteed restore point and then use the archive logs to recover to SCNs from the guaranteed restore point until the time you want to recover to.

Guaranteed Restore Points with Flashback Logging Disabled:

When you create a guaranteed restore points and the flashback database is disabled then the first time a data file block is modified Oracle stores an image of the block before the modification in the flashback logs. Later modifications to the same block are not logged again in the flashback logs unless another guaranteed restore point was created after the block was last modified.
This solution can be used when you want to revert database changes made by the application (during an upgrade for example).
In the following example, we will show you how to use Guaranteed Restore Points with Flashback Logging Disabled to revert database changes in a RAC 11gR2 environment.

The example:

Read the complete post here: www.oracle-class.com

Views: 228

Comment

You need to be a member of Oracle Community to add comments!

Join Oracle Community

Oracle Community On

I'm not a fan of advertising, and so I will not be including any advertisements on OracleCommunity.net. However, managing this community does not come without cost! If you are willing to donate to help pay for the monthly community fees and domain services I accept Bitcoin and PayPal donations.

Donate Bitcoins

Badge

Loading…

Blog Posts

Oracle 12c Features Enforcing Consumers for an Upgrade

Oracle has been one of the most preferred database management systems and has been serving the software development platform at both small-scale and large-scale companies with its advanced data management tools for more than a decade. On delving a bit deeper into the history of DBMSes, you see Oracle as a huge brand name just because of its features; however, the noticeable aspect about Oracle is, the upgrade in its versions are a bit slower compared to other well-known…

Continue

Posted by Prett Sons on April 21, 2014 at 9:45pm

Database hang and Row Cache Lock concurrency troubleshooting

This post will help to analyze Oracle database instance slowdown that can happen due to considerable row cache lock (enqueue) wait events. It’s is based on a real case of a database hang that I worked on recently. I must admit this type of situation does not appear often but it’s very dangerous since it can considerably slow down a database instance or even freeze it for a short period of time. In most cases SQL against ASH view and Systemstate dumps can help to nail down the problem unless…

Continue

Posted by Kirill Loifman on April 15, 2014 at 12:53am

© 2014   Created by Steve Karam.

Badges  |  Report an Issue  |  Terms of Service