各位好:
有一个表t(A,B),表内容如下:
A B
1 y
1 z
2 W
3 R
3 Y
3 P要求是,如查A值相同,就汇总B的值,中间用“_”分隔,如下
A B
1 y_z
2 W
3 R_Y_P我首先考虑的是游标,但各位在没有其他别的方法?多谢了!
有一个表t(A,B),表内容如下:
A B
1 y
1 z
2 W
3 R
3 Y
3 P要求是,如查A值相同,就汇总B的值,中间用“_”分隔,如下
A B
1 y_z
2 W
3 R_Y_P我首先考虑的是游标,但各位在没有其他别的方法?多谢了!
--处理的数据
CREATE TABLE tb(col1 varchar(10),col2 int)
INSERT tb SELECT 'a',1
UNION ALL SELECT 'a',2
UNION ALL SELECT 'b',1
UNION ALL SELECT 'b',2
UNION ALL SELECT 'b',3--合并处理
--定义结果集表变量
DECLARE @t TABLE(col1 varchar(10),col2 varchar(100))--定义游标并进行合并处理
DECLARE tb CURSOR LOCAL
FOR
SELECT col1,col2 FROM tb ORDER BY col1,col2
DECLARE @col1_old varchar(10),@col1 varchar(10),@col2 int,@s varchar(100)
OPEN tb
FETCH tb INTO @col1,@col2
SELECT @col1_old=@col1,@s=''
WHILE @@FETCH_STATUS=0
BEGIN
IF @col1=@col1_old
SELECT @s=@s+','+CAST(@col2 as varchar)
ELSE
BEGIN
INSERT @t VALUES(@col1_old,STUFF(@s,1,1,''))
SELECT @s=','+CAST(@col2 as varchar),@col1_old=@col1
END
FETCH tb INTO @col1,@col2
END
INSERT @t VALUES(@col1_old,STUFF(@s,1,1,''))
CLOSE tb
DEALLOCATE tb
--显示结果并删除测试数据
SELECT * FROM @t
DROP TABLE tb
/*--结果
col1 col2
---------- -----------
a 1,2
b 1,2,3
--*/
GO
/*==============================================*/
--3.3.2 使用用户定义函数,配合SELECT处理完成字符串合并处理的示例
--处理的数据
CREATE TABLE tb(col1 varchar(10),col2 int)
INSERT tb SELECT 'a',1
UNION ALL SELECT 'a',2
UNION ALL SELECT 'b',1
UNION ALL SELECT 'b',2
UNION ALL SELECT 'b',3
GO--合并处理函数
CREATE FUNCTION dbo.f_str(@col1 varchar(10))
RETURNS varchar(100)
AS
BEGIN
DECLARE @re varchar(100)
SET @re=''
SELECT @re=@re+','+CAST(col2 as varchar)
FROM tb
WHERE col1=@col1
RETURN(STUFF(@re,1,1,''))
END
GO--调用函数
SELECT col1,col2=dbo.f_str(col1) FROM tb GROUP BY col1
--删除测试
DROP TABLE tb
DROP FUNCTION f_str
/*--结果
col1 col2
---------- -----------
a 1,2
b 1,2,3
--*/
GO/*==============================================*/
--3.3.3 使用临时表实现字符串合并处理的示例
--处理的数据
CREATE TABLE tb(col1 varchar(10),col2 int)
INSERT tb SELECT 'a',1
UNION ALL SELECT 'a',2
UNION ALL SELECT 'b',1
UNION ALL SELECT 'b',2
UNION ALL SELECT 'b',3--合并处理
SELECT col1,col2=CAST(col2 as varchar(100))
INTO #t FROM tb
ORDER BY col1,col2
DECLARE @col1 varchar(10),@col2 varchar(100)
UPDATE #t SET
@col2=CASE WHEN @col1=col1 THEN @col2+','+col2 ELSE col2 END,
@col1=col1,
col2=@col2
SELECT * FROM #t
/*--更新处理后的临时表
col1 col2
---------- -------------
a 1
a 1,2
b 1
b 1,2
b 1,2,3
--*/
--得到最终结果
SELECT col1,col2=MAX(col2) FROM #t GROUP BY col1
/*--结果
col1 col2
---------- -----------
a 1,2
b 1,2,3
--*/
--删除测试
DROP TABLE tb,#t
GO
/*==============================================*/--3.3.4.1 每组 <=2 条记录的合并
--处理的数据
CREATE TABLE tb(col1 varchar(10),col2 int)
INSERT tb SELECT 'a',1
UNION ALL SELECT 'a',2
UNION ALL SELECT 'b',1
UNION ALL SELECT 'b',2
UNION ALL SELECT 'c',3--合并处理
SELECT col1,
col2=CAST(MIN(col2) as varchar)
+CASE
WHEN COUNT(*)=1 THEN ''
ELSE ','+CAST(MAX(col2) as varchar)
END
FROM tb
GROUP BY col1
DROP TABLE tb
/*--结果
col1 col2
---------- ----------
a 1,2
b 1,2
c 3
--*/--3.3.4.2 每组 <=3 条记录的合并
--处理的数据
CREATE TABLE tb(col1 varchar(10),col2 int)
INSERT tb SELECT 'a',1
UNION ALL SELECT 'a',2
UNION ALL SELECT 'b',1
UNION ALL SELECT 'b',2
UNION ALL SELECT 'b',3
UNION ALL SELECT 'c',3--合并处理
SELECT col1,
col2=CAST(MIN(col2) as varchar)
+CASE
WHEN COUNT(*)=3 THEN ','
+CAST((SELECT col2 FROM tb WHERE col1=a.col1 AND col2 NOT IN(MAX(a.col2),MIN(a.col2))) as varchar)
ELSE ''
END
+CASE
WHEN COUNT(*)>=2 THEN ','+CAST(MAX(col2) as varchar)
ELSE ''
END
FROM tb a
GROUP BY col1
DROP TABLE tb
/*--结果
col1 col2
---------- ------------
a 1,2
b 1,2,3
c 3
--*/
GO
-------------------------------------------> 测试时间:2009-07-20
--> 我的淘宝:http://shop36766744.taobao.com/--------------------------------------------------if object_id('[TB]') is not null drop table [TB]
create table [TB]([A] int,[B] varchar(1))
insert [TB]
select 1,'y' union all
select 1,'z' union all
select 2,'W' union all
select 3,'R' union all
select 3,'Y' union all
select 3,'P'
create function dbo.f_str(@id int) returns varchar(100)
as
begin
declare @str varchar(1000)
set @str = ''
select @str = @str + '_' + cast(B as varchar) from tb where A = @id
set @str = right(@str , len(@str) - 1)
return @str
end
goselect A,dbo.f_str(A) from TB group by A/*
A
----------- ----------------------------------------------------------------------------------------------------
1 y_z
2 W
3 R_Y_P(所影响的行数为 3 行)
*/drop table TB
drop function dbo.f_str
-- -----------t_mac 小编-------------
---希望有天成为大虾----
-- =========================================IF OBJECT_ID('tb') IS NOT NULL
DROP TABLE tb
GO
CREATE TABLE tb( A VARCHAR(10) , B VARCHAR(10))
go
insert tb SELECT
'A' , 'B' UNION ALL SELECT
'1' , 'y' UNION ALL SELECT
'1' , 'z' UNION ALL SELECT
'2' , 'W' UNION ALL SELECT
'3' , 'R' UNION ALL SELECT
'3' , 'Y' UNION ALL SELECT
'3' , 'P'
GO
CREATE FUNCTION dbo.f_tb(@id VARCHAR(10))
RETURNS varchar(8000)
AS
BEGIN
DECLARE @str varchar(8000)
SET @str = ''
SELECT @str = @str + '-' + b FROM tb WHERE A=@id
RETURN STUFF(@str, 1, 1, '')
END
GO
SELECT A, B = dbo.f_tb(A) FROM tb GROUP BY A
drop table tb
drop function dbo.f_tb
go
/*------------
---------- ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
1 y-z
2 W
3 R-Y-P
A B-------*/
合并分拆表数据 整理人:中国风(Roy) 日期:2008.06.06
******************************************************************************************************************************************************/ --> --> (Roy)生成測試數據 if not object_id('Tab') is null
drop table Tab
Go
Create table Tab([Col1] int,[Col2] nvarchar(1))
Insert Tab
select 1,N'a' union all
select 1,N'b' union all
select 1,N'c' union all
select 2,N'd' union all
select 2,N'e' union all
select 3,N'f'
Go 合并表: SQL2000用函数: go
if object_id('F_Str') is not null
drop function F_Str
go
create function F_Str(@Col1 int)
returns nvarchar(100)
as
begin
declare @S nvarchar(100)
select @S=isnull(@S+',','')+Col2 from Tab where Col1=@Col1
return @S
end
go
Select distinct Col1,Col2=dbo.F_Str(Col1) from Tab go SQL2005用XML: 方法1: select
a.Col1,Col2=stuff(b.Col2.value('/R[1]','nvarchar(max)'),1,1,'')
from
(select distinct COl1 from Tab) a
Cross apply
(select COl2=(select N','+Col2 from Tab where Col1=a.COl1 For XML PATH(''), ROOT('R'), TYPE))b 方法2: select
a.Col1,COl2=replace(b.Col2.value('/Tab[1]','nvarchar(max)'),char(44)+char(32),char(44))
from
(select distinct COl1 from Tab) a
cross apply
(select Col2=(select COl2 from Tab where COl1=a.COl1 FOR XML AUTO, TYPE)
.query(' <Tab>
{for $i in /Tab[position() <last()]/@COl2 return concat(string($i),",")}
{concat("",string(/Tab[last()]/@COl2))}
</Tab>')
)b SQL05用CTE: ;with roy as(select Col1,Col2,row=row_number()over(partition by COl1 order by COl1) from Tab)
,Roy2 as
(select COl1,cast(COl2 as nvarchar(100))COl2,row from Roy where row=1
union all
select a.Col1,cast(b.COl2+','+a.COl2 as nvarchar(100)),a.row from Roy a join Roy2 b on a.COl1=b.COl1 and a.row=b.row+1)
select Col1,Col2 from Roy2 a where row=(select max(row) from roy where Col1=a.COl1) order by Col1 option (MAXRECURSION 0)
生成结果:
/*
Col1 COl2
----------- ------------
1 a,b,c
2 d,e
3 f (3 行受影响)
*/
-- -----------t_mac 小编-------------
---希望有天成为大虾----
-- =========================================IF OBJECT_ID('tb') IS NOT NULL
DROP TABLE tb
GO
CREATE TABLE tb( A VARCHAR(10) , B VARCHAR(10))
go
insert tb SELECT
'A' , 'B' UNION ALL SELECT
'1' , 'y' UNION ALL SELECT
'1' , 'z' UNION ALL SELECT
'2' , 'W' UNION ALL SELECT
'3' , 'R' UNION ALL SELECT
'3' , 'Y' UNION ALL SELECT
'3' , 'P'
GO
CREATE FUNCTION dbo.f_tb(@id VARCHAR(10))
RETURNS varchar(8000)
AS
BEGIN
DECLARE @str varchar(8000)
SET @str = ''
SELECT @str = @str + '-' + b FROM tb WHERE A=@id
RETURN STUFF(@str, 1, 1, '')
END
GO
SELECT A, B = dbo.f_tb(A) FROM tb GROUP BY A
drop table tb
drop function dbo.f_tb
go
/*------------
---------- ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
1 y-z
2 W
3 R-Y-P
A B-------*/
as
begin
declare @str varchar(1000)
set @str = ''
select @str = @str + '_' + cast(B as varchar) from tb where A = @id
set @str = right(@str , len(@str) - 1)
return @str
end
调用函数:
select A,dbo.f_str(A) from TB group by A