When you use the NetBackup SQL Client, backups using multiple stripes are restored automatically. Select the object you want to restore and NetBackup finds all of the related backups and restore them. Upon restore, all of the streams must also be available at the same time.
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Conventional backups using multiple streams
Advanced backup methods using multiple streams
Restoring a multiplexed SQL Server backup
Restoring a multistreamed SQL Server backup with fewer devices than it was backed up with