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mysql 将列值转变为列的方法
  资讯来源:海力源码    发布时间:2022-9-17 8:36:31
复制代码 代码如下:     -- 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');     -- 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;

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