更新

Question

我手动更改这些列，提取时间值的时区信息。

我在想Rails框架中是否有使用这两列的内部规则。

手动更改它们是否安全？我正在使用此代码：

module ActiveRecord
  class Base

    before_save :update_autocolumns

    def update_autocolumns

      if (!self.id) #inserting
        if (self.respond_to? :created_at)
          self.created_at = Time.now.ttz
        end
      end

      if (self.respond_to? :updated_at)
        self.updated_at = Time.now.ttz
      end
    end

  end
end

更新

这个“ttz”方法用于从时间列中提取时区：

def ttz
  self.strftime('%a, %d %b %Y %H:%M:%S').to_time
end

Answer 1

是的，您可以查看Timestamps module中的代码。你的代码只是多余的。

这些属性将在更新时自动更新。

def timestamp_attributes_for_update
  [:updated_at, :updated_on]
end

这些属性将在创建时自动更新。

def timestamp_attributes_for_create
  [:created_at, :created_on]
end

这是文档。

  # = Active Record Timestamp
  #
  # Active Record automatically timestamps create and update operations if the
  # table has fields named <tt>created_at/created_on</tt> or
  # <tt>updated_at/updated_on</tt>.
  #
  # Timestamping can be turned off by setting:
  #
  #   config.active_record.record_timestamps = false
  #
  # Timestamps are in UTC by default but you can use the local timezone by setting:
  #
  #   config.active_record.default_timezone = :local
  #
  # == Time Zone aware attributes
  #
  # By default, ActiveRecord::Base keeps all the datetime columns time zone aware by executing following code.
  #
  #   config.active_record.time_zone_aware_attributes = true
  #
  # This feature can easily be turned off by assigning value <tt>false</tt> .
  #
  # If your attributes are time zone aware and you desire to skip time zone conversion to the current Time.zone
  # when reading certain attributes then you can do following:
  #
  #   class Topic < ActiveRecord::Base
  #     self.skip_time_zone_conversion_for_attributes = [:written_on]
  #   end

Rails created_at和updated_at内部框架用法

更新

1 个答案: