各位大哥帮帮忙分析一下。
/* 借用SQL 77 的表结构*/
if object_id('tempdb.dbo.#TB') is not null drop table #TB
go
create table #TB([A] varchar(3),[B] int)
insert #TB
select 'bcd',1 union all
select 'bcde',2 union all
select 'cd',3
----------------------
/* bcd 1
bcde 2
cd 3*/----------------------------
想要的结果是:
---------------------
b 1
c 1
d 1
b 2
c 2
d 2
e 2
c 3
d 3
/* 借用SQL 77 的表结构*/
if object_id('tempdb.dbo.#TB') is not null drop table #TB
go
create table #TB([A] varchar(3),[B] int)
insert #TB
select 'bcd',1 union all
select 'bcde',2 union all
select 'cd',3
----------------------
/* bcd 1
bcde 2
cd 3*/----------------------------
想要的结果是:
---------------------
b 1
c 1
d 1
b 2
c 2
d 2
e 2
c 3
d 3
****拆分一个字符串*********
问题描述:
@str='fds,bbbf,eee,ddd,fff,hhhfg,dddde' 拆分成
col
------------------------
fds
bbbf
eee
ddd
fff
hhhfg
dddde
*/
---方法1:动态
declare @str varchar(500),@aaa varchar(8000)
set @str='fds,bbbf,eee,ddd,fff,hhhfg,dddde'
set @aaa='select * from (select '''+REPLACE(@str,',',''' as str union all select ''')+''') a '
exec(@aaa)
go
--方法2:循环
create table #t(
id varchar(10))
declare @str varchar(300)
set @str='fds,bbbf,eee,ddd,fff,hhhfg,dddde'
declare @i int
declare @len int
set @i = 1
while @i < len(@str+',')
begin
insert #t select substring(@str+',',@i,charindex(',',@str+',',@i)-@i)
set @i = charindex(',',@str+',',@i)+1
end
select * from #t
drop table #t
go
--or
CREATE FUNCTION f_splitSTR(
@s varchar(8000), --待分拆的字符串
@split varchar(10) --数据分隔符
)RETURNS @re TABLE(col varchar(100))
AS
BEGIN
DECLARE @splitlen int
SET @splitlen=LEN(@split+'a')-2
WHILE CHARINDEX(@split,@s)>0
BEGIN
INSERT @re VALUES(LEFT(@s,CHARINDEX(@split,@s)-1))
SET @s=STUFF(@s,1,CHARINDEX(@split,@s)+@splitlen,'')
END
INSERT @re VALUES(@s)
RETURN
END
GO
--方法3:使用临时性分拆辅助表法
CREATE FUNCTION f_splitSTR(
@s varchar(8000), --待分拆的字符串
@split varchar(10) --数据分隔符
)RETURNS @re TABLE(col varchar(100))
AS
BEGIN
--创建分拆处理的辅助表(用户定义函数中只能操作表变量)
DECLARE @t TABLE(ID int IDENTITY,b bit)
INSERT @t(b) SELECT TOP 8000 0 FROM syscolumns a,syscolumns b INSERT @re SELECT SUBSTRING(@s,ID,CHARINDEX(@split,@s+@split,ID)-ID)
FROM @t
WHERE ID<=LEN(@s+'a')
AND CHARINDEX(@split,@split+@s,ID)=ID
RETURN
END
GO
declare @str varchar(500),@aaa varchar(8000)
set @str='fds,bbbf,eee,ddd,fff,hhhfg,dddde'
select * from dbo.f_splitSTR(@str,',')
/*
-----------------------------------
-------T-MAC ---------------------
---------------小编---------------
---------------love 轩--------
-----------------------------------
*/
拆分表:
if not object_id('Tab') is null
drop table Tab
Go
Create table Tab([Col1] int,[COl2] nvarchar(5))
Insert Tab
select 1,N'a,b,c' union all
select 2,N'd,e' union all
select 3,N'f'
Go--SQL2000用辅助表:
if object_id('Tempdb..#Num') is not null
drop table #Num
go
select top 100 ID=Identity(int,1,1) into #Num from syscolumns a,syscolumns b
Select
a.Col1,COl2=substring(a.Col2,b.ID,charindex(',',a.Col2+',',b.ID)-b.ID)
from
Tab a,#Num b
where
charindex(',',','+a.Col2,b.ID)=b.ID --也可用 substring(','+a.COl2,b.ID,1)=','
--2000不使用辅助表
Select
a.Col1,COl2=substring(a.Col2,b.number,charindex(',',a.Col2+',',b.number)-b.number)
from
Tab a join master..spt_values b
ON B.type='p' AND B.number BETWEEN 1 AND LEN(A.col2)
where
substring(','+a.COl2,b.number,1)=','
SQL2005用Xml:select
a.COl1,b.Col2
from
(select Col1,COl2=convert(xml,'<root><v>'+replace(COl2,',','</v><v>')+'</v></root>') from Tab)a
outer apply
(select Col2=C.v.value('.','nvarchar(100)') from a.COl2.nodes('/root/v')C(v))b
SQL05用CTE:--此法roy博客;with roy as
(select Col1,COl2=cast(left(Col2,charindex(',',Col2+',')-1) as nvarchar(100)),Split=cast(stuff(COl2+',',1,charindex(',',Col2+','),'') as nvarchar(100)) from Tab
union all
select Col1,COl2=cast(left(Split,charindex(',',Split)-1) as nvarchar(100)),Split= cast(stuff(Split,1,charindex(',',Split),'') as nvarchar(100)) from Roy where split>''
)
select COl1,COl2 from roy order by COl1 option (MAXRECURSION 0)生成结果:
/*
Col1 COl2
----------- -----
1 a
1 b
1 c
2 d
2 e
3 f
*/
go
create table #TB([A] varchar(10),[B] int)
insert #TB
select 'bcd',1 union all
select 'bcde',2 union all
select 'cd',3 select substring(a.a,t.n,1) as a,a.b
from #TB a,(
select 1 as n union all select 2 union all select 3 union all select 4 union all select 5
union all select 6 union all select 7 union all select 8 union all select 9 union all select 10
) as t
where t.n<=len(a.a)
go
create table tb([A] varchar(10),[B] int)
insert tb
select 'bcd',1 union all
select 'bcde',2 union all
select 'cd',3
goselect
substring(a.A,b.number,1) as a,a.b
from tb a,
master..spt_values b
where b.type='P' and b.number>0
and b.number<=len(a.a) /**
a b
---- -----------
b 1
c 1
d 1
b 2
c 2
d 2
e 2
c 3
d 3(所影响的行数为 9 行)
**/
go
create table #TB([A] varchar(10),[B] int)
insert #TB
select 'bcd',1 union all
select 'bcde',2 union all
select 'cd',3
select
substring(a.[A],b.number+1,1)[A],
[B]
from #TB a,master..spt_values b
where b.type='P' and b.number<len(a.[A])
/*
A B
---- -----------
b 1
c 1
d 1
b 2
c 2
d 2
e 2
c 3
d 3(9 個資料列受到影響)
*/
go
create table #TB([A] varchar(4),[B] int)
insert #TB
select 'bcd',1 union all
select 'bcde',2 union all
select 'cd',3 SELECT TOP 100 ID=IDENTITY(INT,1,1) INTO #NUM FROM SYS.SYSCOLUMNS A,SYS.SYSCOLUMNS B
SELECT
A.b,[VALUE]=SUBSTRING(A.a,B.ID,1)
FROM
#TB A,#NUM B
WHERE
b.id<=len(a.a)
/*
b VALUE
----------- -----
1 b
1 c
1 d
2 b
2 c
2 d
2 e
3 c
3 d
go
create table #TB([A] varchar(4),[B] int)
insert #TB
select 'bcd',1 union all
select 'bcde',2 union all
select 'cd',3 SELECT TOP 100 ID=IDENTITY(INT,1,1) INTO #NUM FROM SYS.SYSCOLUMNS A,SYS.SYSCOLUMNS B
SELECT
A.b,[VALUE]=SUBSTRING(A.a,B.ID,1)
FROM
#TB A,#NUM B
WHERE
b.id <=len(a.a)
/*
b VALUE
----------- -----
1 b
1 c
1 d
2 b
2 c
2 d
2 e
3 c
3 d