class PruneOldEventsWorker
include Sidekiq::Worker
include CronjobQueue
def perform
# Contribution calendar shows maximum 12 months of events.
# Double nested query is used because MySQL doesn't allow DELETE subqueries
# on the same table.
Event.unscoped.where(
'(id IN (SELECT id FROM (?) ids_to_remove))',
Event.unscoped.where(
'created_at < ?',
(12.months + 1.day).ago).
select(:id).
limit(10_000)).
delete_all
end
end