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  • mysql 将列值转变为列的方法(转)

    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');

    Full Textsunameobjectscore
    Edit Delete aaa chinese 67
    Edit Delete aaa math 89
    Edit Delete aaa physical 89
    Edit Delete bbb chinese 67
    Edit Delete bbb math 75
    Edit Delete 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;

    Full Texts
    姓名语文数学物理
    aaa 67 89 89
    bbb 67 75 89


     

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  • 原文地址:https://www.cnblogs.com/usergaojie/p/4079558.html
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