Sql查询以获取基于%输入的值

我有一张像下面这样的桌子

 Board Component Cost

    b1     c1       5
    b1     c2       10
    b2     c3       15
    b3     c4       20
    b3     c5       25
    b4     C6       25
  ---------------------
                  100%

我应该给出输入以从表中获取值，比如

如果输入为20%

输出应该是

 Board Component Cost

    b1      c1      5
    b1      c2     10
    b2      c3     15

 Board Component Cost

    b1      c1      5
    b1      c2     10
    b2      c3     15
    b3      c4     20

如果输入为50%

输出应该是

 Board Component Cost

    b1      c1      5
    b1      c2     10
    b2      c3     15

 Board Component Cost

    b1      c1      5
    b1      c2     10
    b2      c3     15
    b3      c4     20

等等

---

如何首先在sql server中编写查询，因为我们需要对以前的值进行分组和求和，所以您需要一个标识来实现这一点。 我希望你能想出一个。 我创建此表是为了模拟您的情况：

create table mySUM(
id int identity(1,1),
id2 varchar(50),
cost int)

insert into mySUM values
('c1',  5),   ('b1', 10),    ('b2',15),    ('b3',20),    ('b3',25),    ('b4',25)

我有两个选择给你。 这是主要的一个，但是，由于我们正在分组和求和，它将在最后一列中得出求和的结果：

select a.Id, a.id2, sum(b.cost) as totalCost
from mySUM a cross join mySUM b
where b.Id <= a.Id
group by a.Id,a.id2
having sum(b.cost)<=50
order by  a.Id

如果您不想这样做，可以基于上述select的ID在主表上运行select：

select * from mySUM where id in(
    select a.Id
    from mySUM a cross join mySUM b
    where b.Id <= a.Id
    group by a.Id,a.id2
    having sum(b.cost)<=50
)

试试这个

SELECT  t.* ,
        rt.runningTotal
FROM    Test t
        CROSS APPLY ( SELECT    SUM(cost) AS runningTotal
                      FROM      Test
                      WHERE     Board <= t.Board
                                AND Component <= t.Component
                    ) AS rt
WHERE   runningTotal <= 50
ORDER BY t.Board

试试这个：

with CTE (Board, Component ,Cost, rownum)
as
(
SELECT Board,Component, Cost,
ROW_NUMBER() OVER(order by Cost asc, Board asc, Component asc) rownum
  FROM yourTable t0
  where Cost > 0
)
select
t1.Board,t1.Component, t1.Cost, t1.rownum, sum(t2.Cost)
from 
CTE t1 join CTE t2 on t1.rownum >= t2.rownum
group by t1.Board,t1.Component, t1. Cost, t1.rownum
having sum(t2.Cost) < 50
order by t1.rownum;

---

应该以50%的比例工作

，为什么最后两个不行？我们应该从上到下选择？20%不应该是30%吗？你想对部分进行求和，直到达到一定的百分比吗？你想按什么排序？这听起来像是子集求和问题是的，首先我需要从低到高排序，如果是50%，它将列出所有。但是不应该，请检查第二个输出表是的，我确实读得太快了。我改变了我的答案，请看一下当你的问题要求20%时，你返回5+10+15=30。这不应该是5+10=15，因为它比20小吗？如果需要按分数排序，请更改内部Where子句。原来的问题不清楚，虽然你想按字母顺序排列前两列。@Somashekhar也许你可以帮助你的助手，说明哪些不正确

DECLARE @T TABLE (Col1 VARCHAR(10), Col2 VARCHAR(10), Col3 INT, SumValue Int)

INSERT INTO @T(Col1, Col2, Col3)
VALUES ('b1','c1',5)

INSERT INTO @T(Col1, Col2, Col3)
VALUES ('b1','c2',10)

INSERT INTO @T(Col1, Col2, Col3)
VALUES ('b2','c3',15)

INSERT INTO @T(Col1, Col2, Col3)
VALUES ('b3','c4',20)

INSERT INTO @T(Col1, Col2, Col3)
VALUES ('b3','c5',25)

INSERT INTO @T(Col1, Col2, Col3)
VALUES ('b4','C6',25) 

DECLARE @SumValue INT

UPDATE @T
SET @SumValue=SumValue = ISNULL(@SumValue,0)+ Col3
FROM @T T

SELECT *
FROM @T
WHERE SumValue <= (
    SELECT TOP 1 SumValue
    FROM @T AS T
    WHERE T.SumValue>=40
    ORDER BY SumValue)

create table #per(
Board varchar(10),
Component varchar(max),
Cost int)

create proc out_per (
@desire_per int)
as begin

declare @sum int, @count int;
declare @board varchar(max), @component varchar(max);
declare @cost int;
declare per_cursor cursor for
select Board,Component,Cost from per
open per_cursor
fetch next from per_cursor into @Board, @component, @cost
while(@@fetch_status=0)
    begin
        insert into #per values (@Board, @component, @cost);
        set @sum=(select sum(cost) from #per)
        if(@sum>=@desire_per)
        begin
            break;
        end
        fetch next from per_cursor into @Board, @component, @cost
    end
    close per_cursor
    deallocate per_cursor
    select * from #per
    truncate table #per
end

exec out_per @desire_per=30