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  • SQL 行列转置

    Create table Class([Student] nvarchar(2),[Course] nvarchar(2),[Score] int)
    Insert Class
    select N'张三',N'语文',78 union all
    select N'张三',N'数学',87 union all
    select N'张三',N'英语',82 union all
    select N'张三',N'物理',90 union all
    select N'李四',N'语文',65 union all
    select N'李四',N'数学',77 union all
    select N'李四',N'英语',65 union all
    select N'李四',N'物理',85 
    Go
    --2000方法:
    动态:
    
    declare @s nvarchar(4000)
    set @s=''
    Select     @s=@s+','+quotename([Course])+'=max(case when [Course]='+quotename([Course],'''')+' then [Score] else 0 end)'
    from Class group by[Course]
    exec('select [Student]'+@s+' from Class group by [Student]')
    
    
    生成静态:
    
    select 
        [Student],
        [数学]=max(case when [Course]='数学' then [Score] else 0 end),
        [物理]=max(case when [Course]='物理' then [Score] else 0 end),
        [英语]=max(case when [Course]='英语' then [Score] else 0 end),
        [语文]=max(case when [Course]='语文' then [Score] else 0 end) 
    from 
        Class 
    group by [Student]
    
    GO
    --------
    SQL2005方法
    动态:
    
    declare @s nvarchar(4000)
    Select     @s=isnull(@s+',','')+quotename([Course]) from Class group by[Course]
    exec('select * from Class pivot (max([Score]) for [Course] in('+@s+'))b')
    
    生成静态:
    select * 
    from 
        Class 
    pivot 
        (max([Score]) for [Course] in([数学],[物理],[英语],[语文]))b
    View Code
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  • 原文地址:https://www.cnblogs.com/key-ok/p/3359707.html
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