How to back up oracle

In the field of data management, backup and recovery are very critical operations. Oracle is a widely used relational database management system, therefore, backing up the Oracle database is a necessary task to protect its data from various corruptions or failures. In this article, we will introduce how to backup Oracle database to ensure data security and reliability.

1. Backup types

Oracle database supports multiple backup types, as shown below:

1. Full backup: Full backup refers to backing up the entire database. This type of backup includes every table space, control file, and redo log.

2. Incremental backup: Incremental backup refers to backing up only the parts that have changed since the last backup. Incremental backups can save storage space while quickly restoring data.

3. Archive log backup: Archive log backup refers to backing up archived redo log files to ensure the continuity and integrity of the backup data. This type of backup is very important because archive logs can help restore the database to its most recent state.

4. Online backup: Online backup refers to the backup operation when the database is running without shutting down the database. This backup method is more convenient, but you need to pay attention to the backup time and speed.

2. Backup method

There are many methods to choose from for Oracle database backup. Below we will introduce several common backup methods.

1.RMAN backup

RMAN (Recovery Manager) is a backup and recovery tool provided by Oracle that can manage backup and recovery operations. Using RMAN backup can ensure the integrity and consistency of backup data, and compression technology can be used to reduce the size of backup data.

The general steps for RMAN backup are as follows:

(1) Configure the RMAN backup environment

(2) Create an RMAN backup script file, including backup location, backup type, backup frequency, etc. Information

(3) Use backup script to back up database

2.Exp/Imp backup

Exp (Export) and Imp (Import) are Oracle’s standard tools that can Perform data migration, backup and recovery operations between different Oracle databases. This method can create a full database backup or a selected Schema backup, and can be used for data movement across Oracle databases.

The Export command can export the data in the specified table space and save it to an export file. The Import command can import the data in the export file into the specified Oracle database.

The general steps for Exp/Imp backup are as follows:

(1) Create an export file of the data to be exported

(2) Create the same file as the export file in the target database Table space and user

(3) Use the Imp command to import the data in the export file into the target database

3. Physical backup

Physical backup refers to physically transferring the database Files such as data files, control files, and redo logs are copied to the backup device. This method backs up the actual data and structure of the database, allowing data to be restored from the backup quickly and directly. However, this backup method requires a large amount of storage space and the backup time is relatively long.

The general steps for physical backup are as follows:

(1) Stop the Oracle database

(2) Copy the data files, control files and redo logs to the backup device

(3) Start Oracle database

4. Logical backup

Logical backup refers to backing up the logical structure of the database, such as tables, indexes, views, and stored procedures. This method saves space on the backup device, but backup and recovery are slower because the logical structure of the database needs to be re-created.

The general steps for logical backup are as follows:

(1) Export data (using the Exp command) to an export file

(2) Modify, convert and clear as needed Export file content

(3) Import the modified export file (using the Imp command) into the target database

3. Backup strategy

Backup is important for database management components, therefore a suitable backup strategy needs to be developed to protect the data security of the database. Here are several backup strategies:

1. Full backup and incremental backup

While using full backup, you can use incremental backup to save backup time and device space. Perform a full backup once a week or monthly, followed by incremental backups every day. Incremental backups only process changed data, significantly reducing backup time.

2. Periodic backup

Perform backup tasks regularly according to time rules. Perform backup operations at a specific time every day, week, or month. This method is mainly to ensure the integrity and continuity of backup data.

3. Multiple backup combinations

For important databases, you can adopt a multiple backup combination strategy and use multiple types of backup methods to ensure the reliability and security of the backup data. For example, using physical backup and archive log backup can ensure the integrity of the backup data and the continuity of the restored data.

4. Backup Test

The security and reliability of backup data are the core goals of the backup task. Therefore, backup data must be tested to ensure the integrity and recoverability of the backup.

The steps for backup testing are as follows:

(1) Select a test environment, which is preferably a copy of the simulated online environment.

(2) Restore the backup data to the test environment.

(3) Perform some typical operations to test whether the database is back to normal.

(4) Repair the data and perform the operation again to retest whether the database can operate normally.

Through backup testing, errors and problems in backups can be discovered and repaired. In this way, you can ensure that in the event of system disasters and failures, the database can be restored and the loss of time and data minimized.

Conclusion

Backup is a very important task in database management, which can ensure the security and reliability of data. Oracle database supports multiple backup types and methods, and you can choose the appropriate strategy based on actual needs. During the backup process, attention needs to be paid to the integrity and recoverability of the backup data, and backup testing is performed to ensure the reliability of the backup data. Through backup, the impact of data disasters and failures can be greatly reduced, and the stability and reliability of the database system can be improved.

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