mysql 将列值转变为列的方法

转自http://www.jb51.net/article/36497.htm


-- 创建库
CREATE TABLE `rate` (
 `uname` VARCHAR (300),
 `object` VARCHAR (300),
 `score` VARCHAR (300)
);   
 -- 插入数据
INSERT INTO test.rate (uname, object, score)
 VALUES(‘aaa‘, ‘chinese‘, ‘67‘),
 (‘aaa‘, ‘math‘, ‘89‘),
 (‘aaa‘, ‘physical‘, ‘89‘),
 (‘bbb‘, ‘chinese‘, ‘67‘),
 (‘bbb‘, ‘math‘, ‘75‘),
 (‘bbb‘, ‘physical‘, ‘89‘);

unameobjectscore
aaa chinese 67
aaa math 89
aaa physical 89
bbb chinese 67
bbb math 75
bbb physical 89


 
-- 查询
SELECT DISTINCT uname AS ‘姓名‘,
SUM(CASE object
WHEN ‘chinese‘ THEN score END)  AS ‘语文‘,
SUM(CASE object
WHEN ‘math‘ THEN score END)  AS ‘数学‘,
SUM(CASE object
WHEN ‘physical‘ THEN score END)  AS ‘物理‘ FROM rate GROUP BY uname;

姓名语文数学物理
aaa 67 89 89
bbb 67 75 89


 

郑重声明:本站内容如果来自互联网及其他传播媒体,其版权均属原媒体及文章作者所有。转载目的在于传递更多信息及用于网络分享,并不代表本站赞同其观点和对其真实性负责,也不构成任何其他建议。