# File Backup

> eXtremeDB provides the capability for applications using persistent databases to create copies of the data and log files in a background thread while normal database operations proceed uninterrupted. It is the most efficient way of creating a backup of a disk database as it copies data at the file level, sequentially, without interpreting the content of the database pages. Because the file backup copies the physical data and log files, the database is "restored" by simply specifying these backup files in the device definition and opening the database in the normal way.

> There is minimal overhead associated with the file backup procedure as database performance is only affected when the file copy is actually being performed. However it should be noted that very large database files can take a long time to copy, which can have a significant impact on database applications.

> Please use the links below to view detailed explanations and examples for your development environment:

> mco_disk_backup() | File backup in C
> fileBackup() | File backup in C++
> select file_backup() | File backup using SQL
> xSQL filebackup | File backup using xSQL command

> The other native language APIs (Python, Java and C#) allow file backup by calling the SQL function `file_backup()`.