151 karma · joined January 14, 2012
Why did you report the numbers for the United States in ranges?
We have reported the numbers for all criminal and national security requests to the maximum extent permitted by law. We continue to push the United States government to allow more transparency regarding these requests, including specific numbers and types of national security-related requests. We will publish updated information for the United States as soon as we obtain legal authorization to do so.
Also, I mentioned why account deletion is a non-trivial problem in this comment thread last week: https://news.ycombinator.com/item?id=5976947.
But for a large social site, it starts to become a more interesting distributed systems problem.
Even for a simple story with 4 likes, 12 comments, and likes on several of the comments, the data is sharded across several databases. Simple transactions no longer work. One option is looking for scalable distributed transactions. A more likely option is making sure deletions can be interrupted and restarted without losing state.
Now imagine a public figure whose post has tens of thousands of comments and hundreds of thousands likes. You may not be able to load all of those rows in a single request let alone delete them synchronously. Instead, you have to be able to process the deletion incrementally, reading and deleting some of the data then later picking up where you left off the last time you were interrupted.
Interestingly, the order of these operations can also be important. If you're interrupted between deleting a comment and deleting the likes on that comment, will you still be able to find the likes when you restart?
We've put a lot of work into a deletion framework that deals with these and many other issues. We're hoping to share more details about it in the future.
If you happen to have any more details about specific stories that reappeared, I’d love to try and figure out exactly what happened. Admittedly, that may be difficult now that several months have passed.
As one of the other commenters mentioned, your Activity Log is a better place to get a full list of your activity and delete it item-by-item. It also shows posts that Timeline omits and includes other types of content such as likes and comments. This help page may be useful https://www.facebook.com/help/activitylog and you can find your Activity Log at https://www.facebook.com/me/allactivity?privacy_source=activ...
I couldn’t tell from your description, but one possibility is that you only saw and deleted the stories rendered on your Timeline, which is just a summary of your activity.