<div class="codebody" id="code17940"> --行列互转 /** 以学生成绩为例子，比较形象易懂 整理人：中国风(Roy) 日期:2008.06.06 **/ --1、行互列 --> --> (Roy)生成測試數據 if not object_id('Class') is null drop table Class Go 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',65 union all select N'李四',77 union all select N'李四',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 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 生成格式: / Student 数学 物理 英语 语文 ------- ----------- ----------- ----------- ----------- 李四 77 85 65 65 张三 87 90 82 78 (2 行受影响) / ------------------------------------------------------------------------------------------ go --加上总成绩(学科平均分) --2000方法: 动态: declare @s nvarchar(4000) set @s='' Select @s=@s+','''')+' then [Score] else 0 end)' from Class group by[Course] exec('select [Student]'+@s+',[总成绩]=sum([Score]) from Class group by [Student]')--加多一列(学科平均分用avg([Score])) 生成动态: select [Student], [语文]=max(case when [Course]='语文' then [Score] else 0 end), [总成绩]=sum([Score]) --加多一列(学科平均分用avg([Score])) from Class group by [Student] go --2005方法: 动态: declare @s nvarchar(4000) Select @s=isnull(@s+','')+quotename([Course]) from Class group by[Course] --isnull(@s+','') 去掉字符串@s中第一个逗号 exec('select [Student],'+@s+',[总成绩] from (select ,[总成绩]=sum([Score])over(partition by [Student]) from Class) a pivot (max([Score]) for [Course] in('+@s+'))b ') 生成静态: select [Student],[数学],[语文],[总成绩] from (select ,[总成绩]=sum([Score])over(partition by [Student]) from Class) a --平均分时用avg([Score]) pivot (max([Score]) for [Course] in([数学],[语文]))b 生成格式: / Student 数学 物理 英语 语文 总成绩 ------- ----------- ----------- ----------- ----------- ----------- 李四 77 85 65 65 292 张三 87 90 82 78 337 (2 行受影响) / go --2、列转行 --> --> (Roy)生成測試數據 if not object_id('Class') is null drop table Class Go Create table Class([Student] nvarchar(2),[数学] int,[物理] int,[英语] int,[语文] int) Insert Class select N'李四',77,85,65,65 union all select N'张三',87,90,82,78 Go --2000: 动态: declare @s nvarchar(4000) select @s=isnull(@s+' union all ','')+'select [Student],[Course]='+quotename(Name,'''')--isnull(@s+' union all ','') 去掉字符串@s中第一个union all +',[Score]='+quotename(Name)+' from Class' from syscolumns where ID=object_id('Class') and Name not in('Student')--排除不转换的列 order by Colid exec('select from ('+@s+')t order by [Student],[Course]')--增加一个排序 生成静态: select from (select [Student],[Course]='数学',[Score]=[数学] from Class union all select [Student],[Course]='物理',[Score]=[物理] from Class union all select [Student],[Course]='英语',[Score]=[英语] from Class union all select [Student],[Course]='语文',[Score]=[语文] from Class)t order by [Student],[Course] go --2005: 动态: declare @s nvarchar(4000) select @s=isnull(@s+','')+quotename(Name) from syscolumns where ID=object_id('Class') and Name not in('Student') order by Colid exec('select Student,[Course],[Score] from Class unpivot ([Score] for [Course] in('+@s+'))b') go select Student,[Score] from Class unpivot ([Score] for [Course] in([数学],[语文]))b 生成格式: / Student Course Score ------- ------- ----------- 李四 数学 77 李四 物理 85 李四 英语 65 李四 语文 65 张三 数学 87 张三 物理 90 张三 英语 82 张三 语文 78 (8 行受影响) /
