# File lib/ohm.rb, line 636
    def replace(models)
      ids = models.map(&:id)

      model.synchronize do
        redis.queue("MULTI")
        redis.queue("DEL", key)
        ids.each { |id| redis.queue("SADD", key, id) }
        redis.queue("EXEC")
        redis.commit
      end
    end