# This could potentially take a long time, do it in the background
Task.start(fn ->
- q = from a in Activity,
- where: ^old_follower_address in a.recipients,
- update: [set: [recipients: fragment("array_replace(?,?,?)", a.recipients, ^old_follower_address, ^user.follower_address)]]
- Repo.update_all(q, [])
-
q = from u in User,
where: ^old_follower_address in u.following,
update: [set: [following: fragment("array_replace(?,?,?)", u.following, ^old_follower_address, ^user.follower_address)]]
Repo.update_all(q, [])
+
+ # Only do this for recent activties, don't go through the whole db.
+ since = (Repo.aggregate(Activity, :max, :id) || 0) - 100_000
+ q = from a in Activity,
+ where: ^old_follower_address in a.recipients,
+ where: a.id > ^since,
+ update: [set: [recipients: fragment("array_replace(?,?,?)", a.recipients, ^old_follower_address, ^user.follower_address)]]
+ Repo.update_all(q, [])
end)
{:ok, user}