求sql语句

[xiequan2]

表结构如下:
id          idx
----------- ----------
1           A
2           A
3           B
4           B
5           A
6           C
7           D
8           D
9           D
10          D
--建表语句
declare @t table(id int,idx varchar(10))
insert into @t
select 1,'A' union all
select 2,'A' union all
select 3,'B' union all
select 4,'B' union all
select 5,'A' union all
select 6,'C' union all
select 7,'D' union all
select 8,'D' union all
select 9,'D' union all
select 10,'D' 

 

  求sql生成以下结构:

	id idx
	1-2 A
	3-4 B
	5-5 A
	6-6 C
	7-10 D

[水族杰纶]

---參考
SQL code问题描述：
无论是在sql 2000，还是在 sql 2005 中,都没有提供字符串的聚合函数，
  所以，当我们在处理下列要求时，会比较麻烦：
有表tb, 如下：
id    value
----- ------
1     aa
1     bb
2     aaa
2     bbb
2     ccc
需要得到结果：
id     values
------ -----------
1      aa,bb
2      aaa,bbb,ccc
即， group by id, 求 value 的和（字符串相加）

1. 旧的解决方法

-- 1. 创建处理函数
CREATE FUNCTION dbo.f_str(@id int)
RETURNS varchar(8000)
AS
BEGIN
    DECLARE @r varchar(8000)
    SET @r = ''
    SELECT @r = @r + ',' + value
    FROM tb
    WHERE id=@id
    RETURN STUFF(@r, 1, 1, '')
END
GO
-- 调用函数

SELECt id, values=dbo.f_str(id) 
FROM tb 
GROUP BY id

-- 2. 新的解决方法 
-- 示例数据
DECLARE @t TABLE(id int, value varchar(10))
INSERT @t SELECT 1, 'aa'
UNION ALL SELECT 1, 'bb'
UNION ALL SELECT 2, 'aaa'
UNION ALL SELECT 2, 'bbb'
UNION ALL SELECT 2, 'ccc'

-- 查询处理
SELECT *
FROM(
    SELECT DISTINCT 
        id
    FROM @t
)A
OUTER APPLY(
    SELECT 
        [values]= STUFF(REPLACE(REPLACE(
            (
                SELECT value FROM @t N
                WHERE id = A.id
                FOR XML AUTO
            ), '<N value="', ','), '"/>', ''), 1, 1, '')
)N

/*--结果
id          values
----------- ----------------
1           aa,bb
2           aaa,bbb,ccc
(2 行受影响)
--*/

--各种字符串分函数

--3.3.1 使用游标法进行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
--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
if not object_id('A') is null
    drop table A
Go
Create table A([id] int,[cname] nvarchar(2))
Insert A
select 1,N'张三' union all
select 2,N'李四' union all
select 3,N'王五' union all
select 4,N'蔡六'
Go
--> --> 
 
if not object_id('B') is null
    drop table B
Go
Create table B([id] int,[cname] nvarchar(5))
Insert B
select 1,N'1,2,3' union all
select 2,N'3,4'
Go
create function F_str(@cname nvarchar(100))
returns nvarchar(100)
as
begin 
select @cname=replace(@cname,ID,[cname]) from A where patindex('%,'+rtrim(ID)+',%',','+@cname+',')>0
return @cname
end
go
select [id],dbo.F_str([cname])[cname] from B

id          cname
----------- ----------------------------------------------------------------------------------------------------
1           张三,李四,王五
2           王五,蔡六

(2 個資料列受到影響)

[liangCK]

declare @t table(id int,idx varchar(10))
insert into @t
select 1,'A' union all
select 2,'A' union all
select 3,'B' union all
select 4,'B' union all
select 5,'A' union all
select 6,'C' union all
select 7,'D' union all
select 8,'D' union all
select 9,'D' union all
select 10,'D' 

SELECT RTRIM(MIN(id)) + '-' + RTRIM(MAX(id)) AS id,idx
FROM (
    SELECT *,flag = (SELECT COUNT(*) FROM @t 
                     WHERE id < A.id AND idx<>A.idx)
    FROM @t AS A
) AS A
GROUP BY flag,idx
ORDER BY MIN(id)

/*
id                        idx
------------------------- ----------
1-2                       A
3-4                       B
5-5                       A
6-6                       C
7-10                      D

(5 行受影响)

*/

[liangCK]

别乱贴.

[liangCK]

declare @t table(id int,idx varchar(10))
insert into @t
select 1,'A' union all
select 2,'A' union all
select 3,'B' union all
select 4,'B' union all
select 5,'A' union all
select 6,'C' union all
select 7,'D' union all
select 8,'D' union all
select 9,'D' union all
select 10,'D' 

SELECT *,flag=CAST(null AS INT) INTO # FROM @t;

DECLARE @idx VARCHAR(10)
DECLARE @i INT
SET @i = 0

UPDATE # SET
    @i = CASE WHEN idx = @idx THEN @i ELSE @i + 1 END,
    flag = @i,
    @idx = idx;

SELECT RTRIM(MIN(id)) + '-' + RTRIM(MAX(id)) AS id,idx
FROM #
GROUP BY flag,idx
order by MIN(id)

drop table #

/*
id                        idx
------------------------- ----------
1-2                       A
3-4                       B
5-5                       A
6-6                       C
7-10                      D

(5 行受影响)
*/

[Yang_]

declare @t table(id int,idx varchar(10))
insert into @t
select 1,'A' union all
select 2,'A' union all
select 3,'B' union all
select 4,'B' union all
select 5,'A' union all
select 6,'C' union all
select 7,'D' union all
select 8,'D' union all
select 9,'D' union all
select 10,'D' 


select cast(a.id as varchar)+'-'+cast(b.id as varchar),a.idx
from @t a,@t b
where not exists (select 1 from @t where id=a.id-1 and idx=a.idx)
and not exists (select 1 from @t where id=b.id+1 and idx=b.idx)
and a.idx=b.idx
and b.id = (select top 1 id from @t c
where id>=a.id
and idx=a.idx
and not exists (select 1 from @t where id=c.id+1 and idx=c.idx)
order by id 
)

--结果
                                                              idx
------------------------------------------------------------- ----------
1-2                                                           A
3-4                                                           B
5-5                                                           A
6-6                                                           C
7-10                                                          D

(5 行受影响)

[jwdream2008]

[Quote=引用 2 楼 liangck 的回复:]
SQL codedeclare@ttable(idint,idxvarchar(10))insertinto@tselect1,'A'unionallselect2,'A'unionallselect3,'B'unionallselect4,'B'unionallselect5,'A'unionallselect6,'C'unionallselect7,'D'unionallselect8,'D'¡­
[/Quote]
学习！

[qiaoliqing_2006]

4楼太有才了 。。。 顶了

[x2xnet]

2楼的，实在牛。长见识了。