Backup strategies depend on the nature of the database, some DBA utilize third-party tools to perform the backup, such as backing up all raw devices on OS-level to tapes or by NBU. In such case, you must notify the database to stop writing changes to the datafiles during the user-managed backup, otherwise, the datafiles you got could be inconsistent.
In this series, there are four scenarios can be used to perform user-managed backups. For more details, please refer the following articles:
Tags:Backup and Recovery