revelations_by_dates.rb

revelations_by_dates = {}

Revelation.select([:id, :created_at]).find_in_batches(batch_size: 10000) do |revelations|
  revelations.each do |revelation|
    revelations_by_dates[revelation.created_at.to_date.to_s] ||= 0
    revelations_by_dates[revelation.created_at.to_date.to_s] += 1
  end
end; nil

revelations_by_dates.sort.each do |date, revelations_count|
  puts "#{date}\t#{revelations_count}"
end; nil