在论坛中出现的比较难的sql问题：3(row_number函数1)

最近，在论坛中，遇到了不少比较难的sql问题，虽然自己都能解决，但发现过几天后，就记不起来了，也忘记解决的方法了。 所以，觉得有必要记录下来，这样以后再次碰到这类问题，也能从中获取解答的思路。另外，考虑到前2篇太长，看起来不太方便，所以拆分为第3篇

1、分组查询问题 http://bbs.csdn.net/topics/390619682?page=1#post-395835328 例子表结构数据如下：
id status date price
1 1 2013-10-01 218
2 1 2013-10-02 218
3 0 2013-10-03 218
4 0 2013-10-04 238
5 0 2013-10-05 238
6 0 2013-10-06 238
7 0 2013-10-07 258
8 0 2013-10-08 258
9 0 2013-10-09 218

想获取的结果集一：
2013-10-01至2013-10-03 218
2013-10-04至2013-10-06 238
2013-10-07至2013-10-08 258
2013-10-09至2013-10-09 218

想获取的结果集二：
1 2013-10-01至2013-10-02 218
0 2013-10-03至2013-10-03 218
0 2013-10-04至2013-10-06 238
0 2013-10-07至2013-10-08 258
0 2013-10-09至2013-10-09 218

我的解法：

--drop table tb  create table tb(id int,status int,date varchar(10),price int)  insert into tb select 1,  1,      '2013-10-01',  218 union all select 2,  1,      '2013-10-02',  218 union all select 3,  0,      '2013-10-03',  218 union all select 4,  0,      '2013-10-04',  238 union all select 5,  0,      '2013-10-05',  238 union all select 6,  0,      '2013-10-06',  238 union all select 7,  0,      '2013-10-07',  258 union all select 8,  0,      '2013-10-08',  258 union all select 9,  0,      '2013-10-09',  218 --union all --select 10,  0,      '2013-10-10',  218  go    --第一个结果集 ;with t as ( select *,        row_number() over(partition by price order by id) as rownum,        min(id) over(partition by price) as min_id from tb  ),  tt as ( select id,        price,        a.date,        rownum - (id - min_id) as interval from t a  )  select min(date) + '至' + max(date) as date,        price from tt group by price,interval order by 1 /* date	                price 2013-10-01至2013-10-03	218 2013-10-04至2013-10-06	238 2013-10-07至2013-10-08	258 2013-10-09至2013-10-09	218 */   --第2个结果集 ;with t as ( select *,        row_number() over(partition by status,price order by id) as rownum,        min(id) over(partition by status,price) as min_id from tb  ),  tt as ( select id,        price,        a.date,        a.status,        rownum - (id - min_id) as interval from t a  )  select status,min(date) + '至' + max(date),price from tt group by status,price,interval order by 2 /* status date	                    price 1	   2013-10-01至2013-10-02	218 0	   2013-10-03至2013-10-03	218 0	   2013-10-04至2013-10-06	238 0	   2013-10-07至2013-10-08	258 0	   2013-10-09至2013-10-09	218 */

2、MS-SQL 根据实际所需规格table去比对另一个库存table取浪费最少的数据 http://bbs.csdn.net/topics/390619048
情境描述：根据表A里的物料去比对表B,然后表A根据A1括号里两个尺寸浪费最少来将A1替换成最省的物料。

表A用量需求表：Table A

A0(自增长ID) A1(物料编号)
-------------------------------
0 ls001-(900*110)
1 ls002-(200*300)
....

表B库存物料表: B1没有重复，可以当作ID来使用 Table B:

B1(库存物料) B2(规格1) B3（规格2）
----------------------------------------------
ls001-(700*200) 700 200
ls001-(910*140) 910 140
ls001-(920*120) 920 120
... ... ...
ls002-(100*200) 100 200
ls002-(200*350) 200 350
ls002-(220*320) 220 320
...

原理是：ls001取(920*120)的话浪费分别是左边920-900=20，右边120-110=10，总共浪费是30， 是ls001库存规格(700*200)，(910*140)，(920*120)里浪费最少的，ls002同理。

最后A1字段被替换后的效果如下：

A0(自增长ID) A1(物料编号)
-------------------------------
0 ls001-(920*120)
1 ls002-(220*320)
...

各位有什么好的方案或者算法可分享来学习借鉴一下 ^_^

我的解法：

drop table a drop table b  create table a (a0 int,a1 varchar(100),a2 int,a3 int)  insert into a SELECT 0,'ls001-(900*110)',900,110 UNION ALL SELECT 1,'ls002-(200*300)',200,300   create table b (B1 varchar(100),B2 int,B3 int)  insert into b  SELECT 'ls001-(700*200)',700,200 UNION ALL SELECT 'ls001-(910*140)',910,140 UNION ALL SELECT 'ls001-(920*120)',920,120 UNION ALL SELECT 'ls002-(100*200)',100,200 UNION ALL SELECT 'ls002-(200*350)',200,350 UNION ALL SELECT 'ls002-(220*320)',220,320   ;with t as ( select a0,a1,        substring(a1,1,charindex('-',a1)-1) as b1,        a2,a3        --substring(a1,charindex('(',a1)+1, charindex('*',a1)-charindex('(',a1)-1) as b2,        --substring(a1,charindex('*',a1)+1, charindex(')',a1)-charindex('*',a1)-1) as b3         from a ),  tt as ( select t.a0,        t.a1,        b.b1,        row_number() over(partition by t.a1                               order by abs(t.a2-b.b2) + abs(t.a3 - b.b3)) as rownum from b inner join t         on b.b1 like t.b1 + '%' )  select a0,b1 as a1 from tt  where rownum = 1 /* a0	a1 0	ls001-(920*120) 1	ls002-(220*320) */

3、查询出一段数据后判断记录里面的最大id,是否大于值a 查询语句如下： http://bbs.csdn.net/topics/390619191

select top 200 id, ClassId,Name,Price,BoxContain,BoxLength,BoxWidth,BoxHeight,CName,EName,CPack,PhotoFolder,EPack,0.46*(round(((convert(decimal(10,2),BoxLength)*convert(decimal(10,2),BoxWidth) * convert(decimal(10,2),BoxHeight))/1000000),3))*35.32/BoxContain+Price/6*1.08 from ProductData where ClassId=101 and BoxContain >0 and BoxContain is not null and round(((convert(decimal(10,2),BoxLength)*convert(decimal(10,2),BoxWidth) * convert(decimal(10,2),BoxHeight))/1000000),3) >=0 And round(((convert(decimal(10,2),BoxLength)*convert(decimal(10,2),BoxWidth) * convert(decimal(10,2),BoxHeight))/1000000),3) <= 10000 and (0.46*(round(((convert(decimal(10,2),BoxLength)*convert(decimal(10,2),BoxWidth) * convert(decimal(10,2),BoxHeight))/1000000),3))*35.32/BoxContain+Price/6*1.08) >=10 and (0.46*(round(((convert(decimal(10,2),BoxLength)*convert(decimal(10,2),BoxWidth) * convert(decimal(10,2),BoxHeight))/1000000),3))*35.32/BoxContain+Price/6*1.08) <=1000 and EPack='Window Box' order by id asc

我的解法，适用于SQL Server 2000：

select * from  ( select top 200 id, ClassId,Name,Price,BoxContain,BoxLength,BoxWidth,BoxHeight,CName,EName,CPack,PhotoFolder,EPack, 0.46*(round(((convert(decimal(10,2),BoxLength)*convert(decimal(10,2),BoxWidth) * convert(decimal(10,2),BoxHeight))/1000000),3))*35.32/BoxContain+Price/6*1.08  from ProductData  where ClassId=101 and BoxContain >0 and BoxContain is not null  and round(((convert(decimal(10,2),BoxLength)*convert(decimal(10,2),BoxWidth) * convert(decimal(10,2),BoxHeight))/1000000),3) >=0  And round(((convert(decimal(10,2),BoxLength)*convert(decimal(10,2),BoxWidth) * convert(decimal(10,2),BoxHeight))/1000000),3) <= 10000   and (0.46*(round(((convert(decimal(10,2),BoxLength)*convert(decimal(10,2),BoxWidth) * convert(decimal(10,2),BoxHeight))/1000000),3))*35.32/BoxContain+Price/6*1.08) >=10   and (0.46*(round(((convert(decimal(10,2),BoxLength)*convert(decimal(10,2),BoxWidth) * convert(decimal(10,2),BoxHeight))/1000000),3))*35.32/BoxContain+Price/6*1.08) <=1000   and EPack='Window Box'  order by id asc )t where ( 	select max(id)      from 	( 	select top 200 id, ClassId,Name,Price,BoxContain,BoxLength,BoxWidth,BoxHeight,CName,EName,CPack,PhotoFolder,EPack, 	0.46*(round(((convert(decimal(10,2),BoxLength)*convert(decimal(10,2),BoxWidth) * convert(decimal(10,2),BoxHeight))/1000000),3))*35.32/BoxContain+Price/6*1.08  	from ProductData  	where ClassId=101 and BoxContain >0 and BoxContain is not null  	and round(((convert(decimal(10,2),BoxLength)*convert(decimal(10,2),BoxWidth) * convert(decimal(10,2),BoxHeight))/1000000),3) >=0 	 And round(((convert(decimal(10,2),BoxLength)*convert(decimal(10,2),BoxWidth) * convert(decimal(10,2),BoxHeight))/1000000),3) <= 10000  	 and (0.46*(round(((convert(decimal(10,2),BoxLength)*convert(decimal(10,2),BoxWidth) * convert(decimal(10,2),BoxHeight))/1000000),3))*35.32/BoxContain+Price/6*1.08) >=10  	 and (0.46*(round(((convert(decimal(10,2),BoxLength)*convert(decimal(10,2),BoxWidth) * convert(decimal(10,2),BoxHeight))/1000000),3))*35.32/BoxContain+Price/6*1.08) <=1000  	 and EPack='Window Box'           order by id asc 	)t ) > a

本文出自 “探索SQLServer” 博客，请务必保留此出处http://yupeigu.blog.51cto.com/3323001/1367969