1.表数据
2.结果数据
CREATE TABLE `TEST_TB_GRADE` ( `ID` int(10) NOT NULL AUTO_INCREMENT, `USER_NAME` varchar(20) DEFAULT NULL, `COURSE` varchar(20) DEFAULT NULL, `SCORE` float DEFAULT '0', PRIMARY KEY (`ID`)) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;
insert into TEST_TB_GRADE(USER_NAME, COURSE, SCORE) values("张三", "数学", 34),("张三", "语文", 58),("张三", "英语", 58),("李四", "数学", 45),("李四", "语文", 87),("李四", "英语", 45),("王五", "数学", 76),("王五", "语文", 34),("王五", "英语", 89);
行转列SQL:
SELECT user_name , MAX(CASE course WHEN '数学' THEN score ELSE 0 END ) 数学, MAX(CASE course WHEN '语文' THEN score ELSE 0 END ) 语文, MAX(CASE course WHEN '英语' THEN score ELSE 0 END ) 英语FROM test_tb_gradeGROUP BY USER_NAME;
参考: