mybatis的学习Demo.

CREATE TABLE `user` (
  `id` bigint(20) NOT NULL AUTO_INCREMENT COMMENT '自增主键',
  `name` varchar(100) NOT NULL DEFAULT '' COMMENT '姓名',
  `mobile` varchar(16) NOT NULL DEFAULT '' COMMENT '手机号',
  `id_number` varchar(20) NOT NULL DEFAULT '' COMMENT '身份证号码',
  `created_at` datetime NOT NULL DEFAULT CURRENT_TIMESTAMP COMMENT '创建时间',
  `updated_at` datetime NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP COMMENT '更新时间',
  PRIMARY KEY (`id`),
  KEY `ix_id_number` (`id_number`),
  KEY `ix_mobile` (`mobile`),
  KEY `ix_created_at` (`created_at`),
  KEY `ix_updated_at` (`updated_at`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8 COMMENT='user表';

1. 原始的dao开发方法(程序需要开发dao interface 和dao impl)
2. mybatis的mapper接口(相当于dao接口)代理开发方法