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  • MSSQLServer 纵向表转横向表 横向表转纵向表 行转列 列转行

    MSSQLServer 纵向表转横向表  横向表转纵向表

    建表语句及插入数据语句:

    CREATE TABLE Test_y(
        [Name] [nchar](10) NULL,
        [Course] [nchar](10) NULL,
        [Grade] [int] NULL
    ) 
    insert into Test_y values ('张三','语文',75);
    insert into Test_y values ('张三','数学',80);
    insert into Test_y values ('张三','英语',90);
    insert into Test_y values ('李四','语文',90);
    insert into Test_y values ('李四','数学',70);
    insert into Test_y values ('李四','英语',80);
    
    CREATE TABLE Test_x(
        [Name] [nchar](10) NULL,
        [语文] [nchar](10) NULL,
        [数学] [nchar](10) NULL,
        [英语] [nchar](10) NULL
    )
    insert into Test_x values('张三',75,80,90);
    insert into Test_x values('李四',90,70,80);

    纵向表转横向表效果展示:

    纵向表转横向表 sql 语句如下:

    方法一:

    select * from Test_y;
    select Name,
        sum(case Course when '语文' then Grade else 0 end) as 语文,
        sum(case Course when '数学' then Grade else 0 end) as 数学,
        sum(case Course when '英语' then Grade else 0 end) as 英语
        from Test_y group by Name;

    方法二:

    select * From Test_y
        pivot(sum(Grade) for Course IN ([语文],[数学],[英语]))
        AS Test_x;

    横向表转纵向表效果展示:

    横向表转纵向表 sql  语句如下:

    方法一:

    select * from Test_x;
    select Name,'语文' as Course,语文 as Grade
        from Test_x union all
    select Name,'数学' as Course,数学 as Grade
        from Test_x union all
    select Name,'英语' as Course,英语 as Grade
        from Test_x  order by Name desc;

    方法二:

    select Name,Course,Grade from Test_x 
    unpivot(Grade for Course in([数学],[英语],[语文]))as Test_y

    最后谢谢 @漠北水獭 的提示。

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  • 原文地址:https://www.cnblogs.com/fly12300/p/3713766.html
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