Example: Online Restore of a Read-Only File (Simple Recovery Model)
This topic is relevant for SQL Server databases under the simple recovery model that contain a read-only filegroup. Under the simple recovery model, a read-only file can be restored online if a file backup exists that was taken since the file became read-only for the last time.
In this example, a database named
adb contains three filegroups. Filegroup
A is read/write, and filegroups
C are read-only. Initially, all of the filegroups are online. A read-only file in filegroup
b1, has to be restored. The database administrator can restore it by using a backup that was taken after the file became read-only. For the duration of the restore, filegroup
B will be offline, but the remainder of the database will remain online.
The syntax for an online restore sequence is the same as for an offline restore sequence.
To restore the file, the database administrator uses the following restore sequence:
RESTORE DATABASE adb FILE='b1' FROM filegroup_B_backup WITH RECOVERY
The file is now online.