A method, executed by at least one processor, includes generating a snapshot for a plurality of data files, receiving an update request for a selected file of the plurality of data files, determining if the selected file is subject to a backup policy, updating the selected file without preserving the snapshot of the selected file if the selected file is not subject to the backup policy, and updating the selected file while preserving the snapshot of the selected file if the selected file is subject to the backup policy. A corresponding computer program product and computer system are also disclosed herein.