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我只能用多条SQL实现,目前还只能取一列,而不是所有列(但是再变通取多列估计是没有问题的),如果是SQL SERVER 2000 ,好像得用临时表
declare @sql varchar(max)
select @sql=''
select @sql=@sql+cast(B as varchar(1000))+',' from (
select row_number() over( order by b) as id, b from t1 t2 where a=1 ) t
select a , substring(@sql,1 ,len(@sql)-1) as b from t1 where a=1 group by a
-- -----------t_mac 小编-------------
---希望有天成为大虾----
-- =========================================if exists(select * from sys.objects where object_id=(object_ID(N'T1') ))
drop table t1
go
create table T1 ( a int ,b int)
insert T1
select
1, 5 union all select
1, 6 union all select
1 ,7 union all select
3, 2 union all select
3 ,5 union all select
3 ,4 union all select
5, 5 union all select
5 ,4 union all select
5 ,3
go
CREATE FUNCTION dbo.f_tb(@id int)
RETURNS varchar(8000)
AS
BEGIN
DECLARE @str varchar(8000)
SET @str = ''
SELECT @str = @str + ',' + convert(varchar,b) FROM t1 WHERE a=@id
RETURN STUFF(@str, 1, 1, '')
END
GO SELECT a, CardName = dbo.f_tb(a) FROM t1 GROUP BY a
drop table t1
drop function dbo.f_tb
go/*------------
1 5,6,7
3 2,5,4
5 5,4,3
-------*/
--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
Drop table [tb]
Go
Create table [tb]([Emplid] int,[EmplName] nvarchar(2))
Insert tb
Select 10,'张三' union all
Select 11,'李四' union all
Select 12,'王五'
Go
--Select * from tb-->SQL查询如下:
select
stuff((select ','+ltrim(Emplid) from tb for xml path('')),1,1,'') Emplid,
stuff((select ','+ltrim([EmplName]) from tb for xml path('')),1,1,'') [EmplName] /*
Emplid EmplName
-------------------------------- -----------------------------------
10,11,12 张三,李四,王五(1 行受影响)*/
找了个一句的例子
if exists(select * from sys.objects where object_id=(object_ID(N'T1') ))
drop table t1
go
create table T1 ( a int ,b int)
insert T1
select
1, 5 union all select
1, 6 union all select
1 ,7 union all select
3, 2 union all select
3 ,5 union all select
3 ,4 union all select
5, 5 union all select
5 ,4 union all select
5 ,3
go
select * from(select distinct a from T1) A cross apply
(
select b=STUFF(replace(replace(
(
select b from T1 as N
where a=A.a
for XML auto
),'<N b="',','),'"/>',''),1,1,'')
) cc一条语句搞定,sql2000不能这样,2000以上版本都可以
a ,b=stuff(
replace(replace((select b from T1 as N where n.a=t1.a for XML auto ),'<N b="',','),'"/>',''),1,1,null)
from t1 group by aselect
distinct a ,b=stuff(
replace(replace((select b from T1 as N where n.a=t1.a for XML auto ),'<N b="',','),'"/>',''),1,1,null)
from t1