控制台上执行下面的命令

rails g migration addColumnToBlackIps send_time:datetime

会生成文件db/migrate/20210529131328_add_column_to_black_ips.rb

class AddColumnToBlackIps < ActiveRecord::Migration[5.0]
  def change
    add_column :black_ips, :send_time, :datetime
  end
end

执行迁移

rake db:migrate

执行结果

CREATE TABLE `black_ips` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `ip` varchar(255) DEFAULT NULL,
  `created_at` datetime NOT NULL,
  `updated_at` datetime NOT NULL,
  `send_time` datetime DEFAULT NULL,
  PRIMARY KEY (`id`),
  KEY `index_black_ips_on_ip` (`ip`)
) ENGINE=InnoDB AUTO_INCREMENT=6115 DEFAULT CHARSET=utf8;

标签：新字,ip,数据库,Rails,datetime,ips,black,send,NULL
来源： https://www.cnblogs.com/haima/p/14826408.html