求SQL遍历截取字符串
本帖最后由 xxaiwho 于 2013-11-20 18:28:54 编辑 从数据库中读取某一张表（数据若干），然后将某一字段进行截取

比如

字段A 字段B
a/a/c x
a/b/c x


切出来就变成

字段1 字段2 字段3 字段B
a a c x
b b c x


数据不止一条 ，是遍历切取，求完整sql（从读取到遍历到截取到输出），本人小白，求教
[解决办法]
呵呵，写的有点复杂，你看看是这样吗：

if object_id('[tb]') is not null drop table [tb]
go 

create table [tb](A varchar(40),B varchar(10))

insert [tb]
select 'a/a/c','x' union all
select 'a/b/c','x'
go

if OBJECT_ID('tempdb..#temp1') is not null
   drop table #temp1

if OBJECT_ID('tempdb..#temp2') is not null
   drop table #temp2

select *,IDENTITY(int,1,1) id into #temp1
from tb

declare @sql nvarchar(4000)

set @sql = '';

;with t
as
(
select ID,
       SUBSTRING(t.A, number ,CHARINDEX('/',t.a+'/',number)-number) as v,
       b,
       row_number() over(partition by id order by @@servername) as rownum
from #temp1 t,master..spt_values s
where s.number >=1
and s.type = 'P'
and SUBSTRING('/'+t.A,s.number,1) = '/'
)

select * into #temp2
from t


select @sql = @sql + ',max(case when rownum = '+CAST(rownum as varchar)+
                     ' then v else null end) as 列'+CAST(rownum as varchar) 
from #temp2
group by rownum




set @sql = 'select '+STUFF(@sql,1,1,'')+ ',b' +
           ' from #temp2 group by id,b'
           
--select @sql

exec(@sql)   
/*
列1列2列3b
aacx
abcx
*/