データ移行方法

Rakeタスクを実行させる

• migrateファイル

class AddSerialNumberToUsers < ActiveRecord::Migration[6.1]
  def change
    add_column :users, :serial_number, :string, null: false, comment: 'シリアル番号'
  end
end

• lib/tasks/set_serial_nuber_to_users.rake

namespace :user do
  desc "userのserial_numberをセットする"
  task set_serial_numbers: :environment do
    ActiveRecord::Base.transaction do
      # 連番を付与
      User.order(:created_at).find_each do |user|
        user.serial_number = User.generate_serial_number(user.created_at)
        user.save(validate: false)
      end
    end
  end
end

• model
  • serial_numberに連番を付与している

class User < ApplicationRecord
before_create :set_serial_number

def self.generate_serial_number(date = Time.zone.today)
  yymm = Util::TimeStamp.to_s(date, format: '%y%m')

  number = ransack(serial_number_start: yymm).result.count + 1

  yymm + format('%06d', number)
end

private

  def set_serial_number
    self.serial_number = self.class.generate_serial_number
  end
end

• 実行コマンド

bundle exec rake user:set_serial_numbers