Shulou(Shulou.com)05/31 Report--

In this issue, the editor will bring you about the recovery of the three states of redo. The article is rich in content and analyzes and narrates it from a professional point of view. I hope you can get something after reading this article.

CURRENT

(1) if there are archives and backups, incomplete recovery can be used.

SQL > startup mount

SQL > recover database until cancel; first select auto, recover the available archive logs as far as possible, and then execute them again:

SQL > recover database until cancel; enter cancel this time to complete incomplete recovery

Open the data with resetlogs:

SQL > alter database open resetlogs; Open the database

(2) forced recovery, which may lead to data inconsistency

Sql > startup mount

Sql > alter system set "_ allow_resetlogs_corruption" = true scope=spfile

Sql > recover database until cancel

Sql > alter database open resetlogs

With luck, the database can be opened normally, but due to the use of _ allow_resetlogs_corruption mode, the data will be lost, and the state of the database is inconsistent. Therefore, in this case, Oracle recommends exporting the database through EXP. After rebuilding the new database, import it.

INACTIVE

(1) if STATUS is INACTIVE, the archiving has been completed, and the redo log can be cleared directly.

SQL > startup mount

SQL > alter database clear logfile group 3

SQL > alter database open

ACTIVE

(1) if STATUS is ACTIVE, you need to use the following statement to indicate that you are archiving:

SQL > startup mount

SQL > alter database clear unarchived logfile group 3

SQL > alter database open

This is how the recovery of the three states of redo shared by the editor is like. If you happen to have similar doubts, please refer to the above analysis to understand. If you want to know more about it, you are welcome to follow the industry information channel.

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