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  • SQL竖列变横列

    DROP TABLE IF EXISTS curriculumTable;
    
    CREATE TABLE curriculumTable (
      id INT PRIMARY KEY AUTO_INCREMENT,
      NAME VARCHAR(20),
      curriculum VARCHAR(20)
    ) CHARSET=utf8;
    
    INSERT INTO curriculumTable (NAME,curriculum) VALUES ('张三', '语文');
    INSERT INTO curriculumTable (NAME,curriculum) VALUES ('张三', '数学');
    INSERT INTO curriculumTable (NAME,curriculum) VALUES ('张三', '生物');
    INSERT INTO curriculumTable (NAME,curriculum) VALUES ('李四', '语文');
    INSERT INTO curriculumTable (NAME,curriculum) VALUES ('李四', '生物');
    INSERT INTO curriculumTable (NAME,curriculum) VALUES ('王五', '数学');
    INSERT INTO curriculumTable (NAME,curriculum) VALUES ('王五', '生物');
    
    
    SELECT  * FROM curriculumTable ;
    
    
    SELECT id,MAX(CASE curriculum WHEN '语文' THEN NAME ELSE NULL END ) 语文,MAX(CASE curriculum WHEN '数学' THEN NAME ELSE NULL END ) 数学,MAX(CASE curriculum WHEN '生物' THEN NAME ELSE NULL END ) 生物 FROM curriculumTable  GROUP BY id
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  • 原文地址:https://www.cnblogs.com/luoruiyuan/p/9132064.html
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