Pluck in batches - combines the efficiency of pluck with the memory-friendly approach of find_in_batches

pluck_in_batches.rb

module ActiveRecord
  class Relation
    def pluck_in_batches(*columns, batch_size: 1000, start: nil)
      relation = self
      relation = relation.where(table[primary_key].gteq(start)) if start
      batch_order = "#{table.name}.#{primary_key} ASC"
      relation = relation.reorder(batch_order)

      loop do
        batch = relation.limit(batch_size).pluck(*columns, primary_key)
        break if batch.empty?

        yield batch

        break if batch.size < batch_size

        last_value = batch.last.last
        relation = relation.where(table[primary_key].gt(last_value))
      end
    end
  end
end