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  • mysql 行转列

    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_grade
    GROUP BY USER_NAME;
    

     参考:https://www.cnblogs.com/ken-jl/p/8570518.html

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  • 原文地址:https://www.cnblogs.com/zgzf/p/10902037.html
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