activerecord のtimestampにdefault設定をする

• 前提
  • rakeが使えること

table情報を作る

$ bundle exec rake db:create_migration NAME=create_monitoring_logs

ソース更新

$ vi db/migrate/YYYYMMDD014656_create_monitoring_logs.rb

class CreateMonitoringLogs < ActiveRecord::Migration

CREATE_TIMESTAMP = 'DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP'
UPDATE_TIMESTAMP = 'DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP'

  def up
    create_table :monitoring_logs do |t|
      t.integer  :level
      t.bigint  :app_time
      t.text     :body
      t.column :created_at, CREATE_TIMESTAMP
      t.column :updated_at, UPDATE_TIMESTAMP
    end
  end

  def down
    drop_table :monitoring_logs
  end

end

migrateする

$ bundle exec rake db:migrate

table情報を見てみる

$ show create table monitoring_logs;

| monitoring_logs | CREATE TABLE `monitoring_logs` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `level` int(11) DEFAULT NULL,
  `app_time` bigint(20) DEFAULT NULL,
  `body` text,
  `created_at` datetime NOT NULL DEFAULT CURRENT_TIMESTAMP,
  `updated_at` datetime NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1 |

• 結果
  timestampsマジクソだった！