Number of backups can lead to situation where no data will be kept

[bugsyb]

This one falls more under logic change than a bug/crash type of an item though raising it as bug as can lead to serious data loss.

The way the Neo Backup treats backups is separate entries between any type of a data, i.e. one backup can be only app and other can be external data, obb, etc. Running backups separately for each parts creates "backup entries".

Number of backup entries is then taken into account when checking if it didn't pass the set threshold (default 2) and old backups do not need to be removed. If it does, it removes old backups.

This logic, coupled with, i.e. scheduled backups of updated apps can easily lead to removal of app data which will fall outside of the threshold of number of backups to keep.

This shouldn't work that way. Backups should be treated as overall app + data and last backup of all elements should be kept when number of backups gets checked.

Data loss can happen under such scenario:

• number of backups set to 2 (default),
• scheduled backups set for updated apps,
• scheduled backup of data (separate entry) - one can argue that this is source of the problem (logic issue),
• full backup of app and all data taken,
• app update happens,
• updated app backup happens,
• another app update happens,
• updated app backup happens again,
• this leads to situation that initial full backup including all data fall outside of backup count threshold and gets deleted.

We ended up with 2 backups as per current logic and no data for the app.

It would be essential to have logic changed and backup count logic for deletion, should take into account total full set of app & data revisions instead of just entries. This should be default logic as more users can run into it.

One can say, that logic has a flaw as scheduled data backup should be more often that the apk backup and this is true, though to avoid backing up apk every day or i.e. external/obb/media data only the essential data backup might be taken with rest not being backed up more often than every week. This again falls into the same issue, that the other backup entries are deleted whilst should be kept (by type or preferred as proposed that number of revisions including all data types backed up are kept).

Thanks!

[RobertZenz]

That should be related to #699.