gistfile1.rb

def insert_big_arsed_table(array_of_values, created_date)
    
  sql = "COPY big_arsed_table (other_table_id, other_id, other_type, created_at, updated_at) from STDIN WITH DELIMITER AS ',' "

  ActiveRecord::Base.connection_pool.with_connection do |conn|
    rc = conn.raw_connection
    begin
      rc.exec(sql)

      loop_time = Benchmark.ms do 
        array_of_values.each do |u|
          # Spaces are very important here
          line = "#{id},#{u.prop1},#{u.prop2},#{u.prop3},#{created_date}\n"
          rc.put_copy_data(line)
        end
      end

      Rails.logger.info "** Elapsed Loop time: #{loop_time}"

    ensure
      rc.put_copy_end

      result_time = Benchmark.ms do 
        while res = rc.get_result # This takes FOREVA
        end
      end
      Rails.logger.info "** Elapsed Result time: #{result_time}"
    end
  end
end