What are the methods for backing up and restoring data in Oracle?

There are several methods for Oracle data backup and recovery:

1. Cold Backup: Copying database files (such as data files, control files, and log files) to a backup device while the database is closed. When recovering, replace the original files with the backup files.
2. Hot Backup: Backing up database files using the database’s backup tool or the operating system’s file copying tool while the database is running. The database continues to operate without interruption during the backup. To restore, simply replace the original files with the backed-up files.
3. Exporting database: Utilize tools provided by Oracle, such as expdp, to export data from the database into a readable format, such as SQL statements or binary files, and save them to a backup device. When restoring, the exported files can be used to reload the data.
4. Database import: Use tools provided by Oracle (such as impdp) to import exported data files into the database. During recovery, the imported files can be used to restore the data in the database.
5. Archive Recovery: Restoring a database using archived logs. During normal operation, Oracle records changes made to the database in archive logs. When the database experiences a failure or needs to be restored, archived logs can be used to recover to a specific point in time.
6. Database duplication involves copying the data and structure of one database to another for the purpose of backup and recovery. This can be used to create a replica of the database or for database migration.

The above are common methods for backing up and restoring Oracle data. Depending on specific needs and scenarios, choose the appropriate method for backup and recovery operations.