假设有张学生成绩表(t)如下: Name Subject Result 张三 语文 73 张三 数学 83 张三 物理 93 李四 语文 74 李四 数学 84 李四 物理 94 想变成 姓名 语文 数学 物理 张三 73 83 93 李四 74 84 94 代码 create table #t ( Name varchar(10) , Subject varchar(
假设有张学生成绩表(t)如下:
Name Subject Result
张三 语文 73
张三 数学 83
张三 物理 93
李四 语文 74
李四 数学 84
李四 物理 94
想变成
姓名 语文 数学 物理
张三 73 83 93
李四 74 84 94
代码
create table #t
(
Name varchar(10) ,
Subject varchar(10) ,
Result int
)
insert into #t(Name , Subject , Result) values('张三','语文','73')
insert into #t(Name , Subject , Result) values('张三','数学','83')
insert into #t(Name , Subject , Result) values('张三','物理','93')
insert into #t(Name , Subject , Result) values('李四','语文','74')
insert into #t(Name , Subject , Result) values('李四','数学','83')
insert into #t(Name , Subject , Result) values('李四','物理','93')
declare @sql varchar(8000)
set @sql = 'select Name as 姓名'
select @sql = @sql + ' , sum(case Subject when ''' + Subject + ''' then Result end) [' + Subject + ']'
from (select distinct Subject from #t) as a
set @sql = @sql + ' from #t group by name'
exec(@sql)
drop table #t
--结果
姓名 数学 物理 语文
---------- ----------- ----------- -----------
李四 83 93 74
张三 83 93 73
如果上述两表互相换一下:即
姓名 语文 数学 物理
张三 73 83 93
李四 74 84 94
想变成
Name Subject Result
张三 语文 73
张三 数学 83
张三 物理 93
李四 语文 74
李四 数学 84
李四 物理 94
代码
create table #t
(
姓名 varchar(10) ,
语文 int ,
数学 int ,
物理 int
)
insert into #t(姓名 , 语文 , 数学 , 物理) values('张三',73,83,93)
insert into #t(姓名 , 语文 , 数学 , 物理) values('李四',74,84,94)
select 姓名 as Name,'语文' as Subject,语文 as Result from #t union
select 姓名 as Name,'数学' as Subject,数学 as Result from #t union
select 姓名 as Name,'物理' as Subject,物理 as Result from #t
order by 姓名 desc
drop table #t
Name Subject Result
---------- ------- -----------
张三 数学 83
张三 物理 93
张三 语文 73
李四 数学 84
李四 物理 94
李四 语文 74
(所影响的行数为 6 行)
,
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