How to turn off archiving in Oracle

Oracle is a highly reliable database management system that provides multiple protection mechanisms for data security. Among them, archive log is an important mechanism that allows users to restore and back up the database. But sometimes, it is necessary to turn off archiving, such as for testing and development in non-production environments. Here's how to turn off archiving in Oracle.

The first step is to confirm the status of the archive mode

In Oracle, the archive mode has two states: on and off. You can check the current archive mode status through the following command:

ARCHIVE LOG LIST;

If the displayed result is similar to the following, then the archive mode is already on:

Database log mode                Archive Mode
Automatic archival               Enabled
Archive destination              USE_DB_RECOVERY_FILE_DEST
Oldest online log sequence       10
Next log sequence to archive     12
Current log sequence             12

At this time, if you want to close the archive mode, the following operations are required.

Second step, turn off automatic archiving

In the process of turning off archiving, you first need to turn off the automatic archiving function. In Oracle, automatic archiving is implemented by setting up backups of log files over time. The automatic archiving function can be turned off by using the following command:

ALTER DATABASE NOARCHIVELOG;

After executing the above command, the system will prompt that the database instance needs to be restarted for this parameter to take effect. In actual operation, the database instance can be stopped and restarted to make this parameter take effect.

The third step is to clear the archive logs

After turning off automatic archiving, you need to clear all currently existing archive logs. If this step is performed incorrectly, the system may not be able to correctly identify the log files, causing problems when restoring or backing up the system. Clearing the archive logs can be achieved with the following command:

ALTER SYSTEM SWITCH LOGFILE;

Please note that this step needs to be performed on all instances of the database instance to ensure that the necessary archive logs have been cleared.

The fourth step, backup log

After the archive is closed, the last archive log should be backed up. This backup version should be the latest to prevent partial data loss in the database. The backup operation may require the use of third-party tools for backup based on actual conditions.

At this point, the archive has been successfully closed and operations such as testing and development can be carried out as required. If you need to reopen archiving, you can perform the above steps in reverse order.

Summary

Archive mode in Oracle is an important mechanism for protecting the integrity and security of the database. Closing the archive is a normal operation, such as in test and development environments. Turning off archiving can be achieved by turning off automatic archiving, clearing archive logs, and backing up logs. In actual operation, please be sure to pay attention to the importance of backup, checking and testing to ensure that turning off archiving will not affect the use and operation of the database.

The above is the detailed content of How to turn off archiving in Oracle. For more information, please follow other related articles on the PHP Chinese website!