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  • SQL列转行

    生成

    sql代码

     
    生成静态:
    select *
    from (select sname,[Course ] ='数学',[Score]=[数学] from Tb_students union all
    select sname,[Course]='英语',[Score]=[英语] from Tb_students union all
    select sname,[Course]='语文',[Score]=[语文] from Tb_students)t
    order by sname,case [Course] when '语文' then 1 when '数学' then 2 when '英语' then 3 end
    go
     --列转行的静态方案:UNPIVOT,sql2005及以后版本
     
      SELECT sname,Subject, grade
      from dbo.Tb_students
      unpivot(grade for Subject in([语文],[数学],[英语]))as up
      GO
      
      
      --列转行的动态方案:UNPIVOT,sql2005及以后版本
      --因为行是动态所以这里就从INFORMATION_SCHEMA.COLUMNS视图中获取列来构造行,同样也使用了XML处理。
     declare @s nvarchar(4000)
    select @s=isnull(@s+',','')+quotename(Name)
    from syscolumns where ID=object_id('Tb_students') and Name not in('sname')
    order by Colid
    exec('select sname,[Subject],[grade] from Tb_students unpivot ([grade] for [Subject] in('+@s+'))b')
    
    go
    select
        sname,[Subject],[grade]
    from
        Tb_students
    unpivot
        ([grade] for [Subject] in([数学],[英语],[语文]))b
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  • 原文地址:https://www.cnblogs.com/Warmsunshine/p/3619059.html
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