tonilin

# Reference: 
#  1. https://gist.github.com/siannopollo/03d646eb7525f7fce678#file-pluck_in_batches-rb
#  2. https://github.com/rails/rails/blob/master/activerecord/lib/active_record/relation/batches.rb

class ActiveRecord::Relation
  # pluck_in_batches:  yields an array of *columns that is at least size
  #                    batch_size to a block.
  #
  #                    Special case: if there is only one column selected than each batch
  #                                  will yield an array of columns like [:column, :column, ...]