Mysql如何按照日期对比数据

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-- 生成日期: 2016-08-24 00:16:24
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SET SQL_MODE = "NO_AUTO_VALUE_ON_ZERO";
SET time_zone = "+00:00";


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--
-- 数据库: `student`
--

-- --------------------------------------------------------

--
-- 表的结构 `student`
--

CREATE TABLE IF NOT EXISTS `student` (
  `id` varchar(20) NOT NULL,
  `name` varchar(50) NOT NULL,
  `fraction` int(20) NOT NULL,
  `date` date NOT NULL
) ENGINE=MyISAM DEFAULT CHARSET=latin1;

--
-- 转存表中的数据 `student`
--

INSERT INTO `student` (`id`, `name`, `fraction`, `date`) VALUES
('1', 'student', 100, '2016-08-23'),
('1', 'student', 95, '2016-08-22'),
('2', 'student2', 100, '2016-08-23'),
('2', 'student2', 200, '2016-08-22'),
('3', 'student3', 350, '2016-08-23'),
('3', 'student3', 450, '2016-08-22'),
('4', 'student4', 50, '2016-08-23'),
('4', 'student4', 100, '2016-08-22'),
('5', 'student5', 900, '2016-08-23'),
('5', 'student5', 930, '2016-08-22');

/*!40101 SET CHARACTER_SET_CLIENT=@OLD_CHARACTER_SET_CLIENT */;
/*!40101 SET CHARACTER_SET_RESULTS=@OLD_CHARACTER_SET_RESULTS */;
/*!40101 SET COLLATION_CONNECTION=@OLD_COLLATION_CONNECTION */;

MYSQL中的数据

需求:
按照下面最终目的
对比 昨天和前天的数据
（因为每天都要对比最近两天的数据）

需要sql查询语句来实现以下效果

---

select t_22.name, t_22.fraction, t_23.fraction
from (select name, fraction from student where data='2016-08-22') t_22, (select name, fraction from student where data='2016-08-23') t_23
where t_22.name=t_23.name

有空再看看能不能优化
吐槽:题主的id等于没用,id一般用来做主键必然是唯一性的...

---

select t1.name as 姓名
, t1.fraction as 昨天分数
, t2.fraction as 前天分数
, current_date as 今天日期
from
(
select id,name,fraction from student
where date = (current_date - interval 1 day) -- 昨天
) t1
left outer join
(
select id,fraction from student
where date = (current_date - interval 2 day) -- 前天
) t2
on t1.id = t2.id