how can youtube recover channels that were deleted by hackers if deleting a channel deletes the videos “permanently”?
In: Technology
Backups, and sometimes, systems do not delete the data directly, but only flag it as deleted in their databases. The software might actually delete it during a scheduled clean-up or if other requirements are met. Database design can be tricky:
Imagine you count all eggs in the supermarket using a database. Lets say you have counting devices on the shelves and in each shopping cart. Then you want to remove eggs from the supermarket’s inventory.
You can remove all eggs from the shelves, so no new eggs end up in the shopping carts. But you shouldn’t delete the entry in the database yet, because some eggs might still driving around in the shopping carts. The counting devices would get an error if the want to update the number of eggs if the entry is directly removed, the database would say “Eggs? I don’t have an entry for that!”. So you have to design some rule like “Delete entries from the database only after ALL shopping carts passed the cashier, are therefore empty and therefore no eggs are in shopping carts anymore” to keep the database going without errors.
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