The recommended file extension for secondary data files is .ndf. Secondary files store user data. They are optional, user-defined. Secondary files can spread data across disks by putting each file on ...
The recommended file extension for secondary data files is .ndf. Secondary files store user data. They are optional, user-defined. Secondary files can spread data across disks by putting each file on a separate disk. If a database exceeds the maximum file size, secondary files allow continued growth.
NDF files store user data. SQL Server needs the primary MDF file to open NDF files. NDFs typically use different disks than MDFs. But they share filenames like “mydb.mdf” and “mydb.ndf”.
SQL Server stores user data in the primary MDF file. NDF files provide optional secondary storage. Use NDFs when MDFs reach full capacity. Store them on other disks to spread data.
The NDF file format varies. Most are database or data files. Some store faces for detection or lists for verification. Analyze an NDF by dragging it to this page. That will show the file’s details.
If an NDF file has errors, ask the sender to resend it. Data may have been lost when copying the file. That could block accessing it.