[sahila]

How do you manage deleting data from backups? Do you know not take backups?

[crdrost]

"When data subjects exercise one of their rights, the controller must respond within one month. If the request is too complex and more time is needed to answer, then your organisation may extend the time limit by two further months, provided that the data subject is informed within one month after receiving the request."

Backup retention policy 60 days, respond within a week or two telling someone that you have purged their data from the main database but that these backups exist and cannot be changed, but that they will be automatically deleted in 60 days.

The only real difficulty is if those backups are actually restored, then the user deletion needs to be replayed, which is something that would be easy to forget.

[Gigachad]

Probably most just ignore backups. But there were some good proposals where you encrypt every users data with their own key. So a full delete is just deleting the users encryption key, rendering all data everywhere including backups inaccessible.

[jandrewrogers]

Deletion via encryption only works if every user’s data is completely separate from every other user’s data in the storage layer. This is rarely the case in databases, indexes, etc. It also is often infeasible if the number of users is very large (key schedule state alone will blow up your CPU cache).

Databases with data from multiple users largely can’t work this way unless you are comfortable with a several order of magnitude loss of performance. It has been built many times but performance is so poor that it is deemed unusable.

[liamYC]

Smart, how do you backup the users encryption keys?

[Trasmatta]

Most companies don't keep all backups in perpetuity, and instead have rolling backups over some period of time.

[alisonatwork]

Backups can have a fixed retention period.

[sahila]

Sure, but now when the backup is restored two weeks later, is the user redeleted or just forgotten about?