行數據轉換成列數據

示例1

Code	name	Value
1	name1	20
2	name1	30
1	name2	30
2	name2	30
3	name3	20
1	name3	20
2	name3	30
Code	Name1	Name2	Name3
1	20	30	20
2	30	30	30
3	0	0	20

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select code ,sum(case when name ='name1' then Value else 0 end )as name1,
sum(case when name ='name2' then Value else 0 end )as name2,
sum(case when name ='name3' then Value else 0 end )as name3
from tb1 group by code

示例2
表:

id  sid           course  result

1   2005001 语文     80.0
2   2005001 数学     90.0
3   2005001 英语     80.0
4   2005002 语文     56.0
5   2005002 数学     69.0
6   2005002 英语     89.0

执行

select sid,语文=isnull(sum(case course when '语文' then result end),0),
   数学=isnull(sum(case course when '数学' then result end),0),
   英语=isnull(sum(case course when '英语' then result end),0)
   from result
   group by sid
   order by sid 

得出结果

sid           语文 数学 英语

2005001  80.0  90.0  80.0
2005002  56.0  69.0  89.0

示例3
create table #abcd(Mid int,  LossType varchar(50),  LossTime numeric(18,2))

insert into #abcd
select 1,'A','0.1'
union all select 1,'B','0.2'
union all select 1,'A','0.3'
union all select 1,'C','0.1'
union all select 2,'B','0.1'
union all select 2,'B','0.2'
union all select 3,'A','0.2'

declare @sql varchar(2000)
set @sql =''
select @sql =@sql +','+lossType+' =sum(case LossType when '+QUOTENAME(LossType,'''')+' then LossTime else 0 end)'
''''''select @sql =@sql +',sum(case  when LossType = '''+lossType+''' then LossTime else null end) as '+LossType+''
from
(select distinct LossType from #abcd) a
exec(
'select mid '+@sql+' from #abcd group by mid')
select * from #abcd