我需要根据Category列对一组行进行分组，并将基于SUM(Number)列的组合行限制为小于或等于@Limit值。
对于每个不同的Category列，我需要识别＆lt; = @limit的“桶”。如果Number列的所有行的SUM（Category）都是＆lt; = @Limit，那么Category值只会有1个存储桶（如'CCCC' '在样本数据中）。但是，如果SUM（Number）＆gt; @limit，则Category值将存在多个存储桶行（如示例数据中的“AAAA”），并且每个存储桶必须为＆LT; = @Limit。根据需要可以有多个桶。另外，查看Category值'DDDD'，它的一行全部大于@Limit，并在结果集中分成两行。
鉴于此简化数据：
DECLARE @Detail table (DetailID int primary key, Category char(4), Number int)
SET NOCOUNT ON
INSERT @Detail VALUES ( 1, 'AAAA',100)
INSERT @Detail VALUES ( 2, 'AAAA', 50)
INSERT @Detail VALUES ( 3, 'AAAA',300)
INSERT @Detail VALUES ( 4, 'AAAA',200)
INSERT @Detail VALUES ( 5, 'BBBB',500)
INSERT @Detail VALUES ( 6, 'CCCC',200)
INSERT @Detail VALUES ( 7, 'CCCC',100)
INSERT @Detail VALUES ( 8, 'CCCC', 50)
INSERT @Detail VALUES ( 9, 'DDDD',800)
INSERT @Detail VALUES (10, 'EEEE',100)
INSERT @Detail VALUES (11, 'AAAA',200) --EDIT added
INSERT @Detail VALUES (12, 'AAAA',200) --EDIT added
INSERT @Detail VALUES (13, 'AAAA',200) --EDIT added
INSERT @Detail VALUES (14, 'AAAA',200) --EDIT added
SET NOCOUNT OFF
DECLARE @Limit int
SET @Limit=500
我需要以下结果集之一：
DetailID Bucket | DetailID Category Bucket
-------- ------ | -------- -------- ------
1 1 | 1 'AAAA' 1
2 1 | 2 'AAAA' 1
3 1 | 3 'AAAA' 1
4 2 | 4 'AAAA' 2
11 2 | 11 'AAAA' 2 --EDIT added
12 3 | 12 'AAAA' 3 --EDIT added
13 3 | 13 'AAAA' 3 --EDIT added
14 4 | 14 'AAAA' 4 --EDIT added
5 5 OR 5 'BBBB' 1
6 6 | 6 'CCCC' 1
7 6 | 7 'CCCC' 1
8 6 | 8 'CCCC' 1
9 7 | 9 'DDDD' 1
9 8 | 9 'DDDD' 2
10 9 | 10 'EEEE' 1
如果基于集合的解决方案的所有尝试都不能按需运行，我将对@GalacticJello Answer进行修改，修改在下面的代码中注明。我基本上找到了整个类别适合存储桶的所有行，并使用单个INSERT-SELECT插入它们，然后使用@GalacticJello游标循环遍历其余数据。这在我的情况下可以正常工作，因为循环几乎不会有任何行处理。
DECLARE @DetailTemp table (PID INT IDENTITY(1,1), DetailID int primary key, Category char(4), Number int)
DECLARE @DetailFinal table (DetailID int, Category char(4), Bucket int) ---<<<renamed column to Bucket
DECLARE @DetailCount int
SET @DetailCount = 0;
--------<<<optimization added starts here
;WITH AllSingleBuckets AS (
SELECT
Category
FROM @Detail
GROUP BY Category
HAVING SUM(Number)<=@Limit
)
INSERT INTO @DetailFinal
(DetailID, Category, Bucket)
SELECT
d.DetailID,d.Category,1
FROM @Detail d
INNER JOIN AllSingleBuckets s ON d.Category=s.Category
--------<<<optimization added ends here
INSERT @DetailTemp
--------<<<changed for optimization, added WHERE clause
SELECT d.DetailId, d.Category, d.Number FROM @Detail d WHERE NOT EXISTS (SELECT 1 FROM @DetailFinal f WHERE d.Category=f.Category) ORDER BY Category, DetailId
SELECT @DetailCount = @@ROWCOUNT
DECLARE @CurrentPid int
SET @CurrentPid = 1
DECLARE @ThisId int
DECLARE @ThisCategory char(4)
DECLARE @ThisNumber int
DECLARE @CurrentCategory char(4)
DECLARE @CurrentSum INT
DECLARE @CurrentBucket INT
WHILE @CurrentPid <= @DetailCount
BEGIN
SELECT @ThisId = DetailId, @ThisCategory = Category, @ThisNumber = Number
FROM @DetailTemp
WHERE PID = @CurrentPid
IF @ThisCategory = @CurrentCategory
BEGIN
IF @CurrentSum + @ThisNumber > @Limit
BEGIN
SET @CurrentBucket = @CurrentBucket + 1
SET @CurrentSum = @ThisNumber
END
ELSE
BEGIN
SET @CurrentSum = @CurrentSum + @ThisNumber
END
END
ELSE
BEGIN
SET @CurrentBucket = 1
SET @CurrentCategory = @ThisCategory
SET @CurrentSum = @ThisNumber
END
WHILE @CurrentSum > @Limit
BEGIN
INSERT @DetailFinal SELECT @ThisId, @CurrentCategory, @CurrentBucket
SET @CurrentBucket = @CurrentBucket + 1
SET @CurrentSum = @CurrentSum - @Limit
END
INSERT @DetailFinal SELECT @ThisId, @CurrentCategory, @CurrentBucket
SET @CurrentPid = @CurrentPid + 1
END
SELECT * from @DetailFinal ORDER BY Category --------<<<added order by
输出：
DetailID Category Bucket
----------- -------- -----------
1 AAAA 1
2 AAAA 1
3 AAAA 1
4 AAAA 2
11 AAAA 2
12 AAAA 3
13 AAAA 3
14 AAAA 4
5 BBBB 1
6 CCCC 1
7 CCCC 1
8 CCCC 1
9 DDDD 1
9 DDDD 2
10 EEEE 1
(15 row(s) affected)
答案 0 :(得分：1)
可能以下内容对您有用（但它不会为'DDDD'生成2行;我不确定您是否可以在不插入2个不同行的情况下执行此操作。）
select detailId, category,
FLOOR((SELECT sum(Number)
from Detail where category=t2.category and detailId <= t2.detailId
)/501)+1 as bucket
from Detail t2
order by detailId;
答案 1 :(得分：1)
您需要保持运行总计才能知道何时达到@Limit。当然，CROSS APPLY可能无法扩展（并且也取决于索引）。
编辑：固定DDDD，存储桶1
;WITH cRunning AS
(
SELECT
D1.DetailID, D1.Category, D3.RunningTotal, D3.GroupCount
FROM
@Detail D1
CROSS APPLY
(SELECT
Category, COUNT(*) AS GroupCount,
CAST(SUM(Number) AS int) AS RunningTotal
FROM @Detail D2
WHERE D1.Category = D2.Category AND D1.DetailID >= D2.DetailID
GROUP BY D2.Category) D3
)
SELECT
DetailID, Category,
RunningTotal / @Limit + 1 AS Bucket --abuse integer math
FROM
cRunning
UNION ALL
SELECT --singletons > @Limit
DetailID, Category, 1
FROM
cRunning
WHERE
GroupCount = 1 AND RunningTotal > @Limit
ORDER BY
Category, DetailID, Bucket
当然，如果您为DDDD
投入虚拟零行，我的第一个答案就有效...
INSERT @Detail VALUES ( xxx, 'DDDD',0)
...
SELECT
D1.DetailID, D1.Category,
RunningTotal / @Limit + 1 AS Bucket --abuse integer math
FROM
@Detail D1
CROSS APPLY
(SELECT SUM(Number) AS RunningTotal
FROM @Detail D2
WHERE D1.Category = D2.Category AND D1.DetailID >= D2.DetailID
GROUP BY D2.Category) D3
答案 2 :(得分：1)
最后！
我发现了我的代码中的一些错误，纠正了这些错误，现在我通过CTE进行了此操作。我认为，如果一个细节跨越多个桶，那么它将始终在它们之间分开。看起来你现在想要那些比桶更大的桶来跨越多个桶，但其他细节要完全推进到下一个桶。你意识到在这种情况下，你最终可能会在一个桶中装满50个，对吧？如果下一个细节是500，那么它将向前推进，而50将获得一个桶自己 - 宽敞！
无论如何，只要将代码包含在此处作为基于完全设置的解决方案，以防任何人感兴趣：
;WITH sequence_ids AS (SELECT DetailID, Category, Number, ROW_NUMBER() OVER (PARTITION BY Category ORDER BY DetailID) AS sequence_id FROM @Detail),
main_cte AS (
SELECT
D1.DetailID,
D1.Category,
D1.Number,
CASE WHEN @Limit > D1.Number THEN @Limit - D1.Number ELSE 0 END AS RemainingBucket,
CASE WHEN D1.Number > @Limit THEN D1.Number - @Limit ELSE 0 END AS RemainingDetail,
D1.sequence_id,
1 AS bucket
FROM
sequence_ids D1
WHERE
sequence_id = 1
UNION ALL
SELECT
D2.DetailID,
D2.Category,
D2.Number,
CASE WHEN COALESCE(NULLIF(RemainingBucket, 0), @Limit) > COALESCE(NULLIF(main_cte.RemainingDetail, 0), D2.Number) THEN COALESCE(NULLIF(RemainingBucket, 0), @Limit) - COALESCE(NULLIF(main_cte.RemainingDetail, 0), D2.Number) ELSE 0 END AS RemainingBucket,
CASE WHEN COALESCE(NULLIF(main_cte.RemainingDetail, 0), D2.Number) > COALESCE(NULLIF(RemainingBucket, 0), @Limit) THEN COALESCE(NULLIF(main_cte.RemainingDetail, 0), D2.Number) - COALESCE(NULLIF(RemainingBucket, 0), @Limit) ELSE 0 END AS RemainingDetail,
D2.sequence_id,
CASE WHEN RemainingBucket = 0 THEN bucket + 1 ELSE bucket END
FROM
main_cte
INNER JOIN sequence_ids D2 ON
D2.Category = main_cte.Category AND
((main_cte.RemainingDetail > 0 AND D2.DetailID = main_cte.DetailID) OR
(main_cte.RemainingDetail <= 0 AND D2.sequence_id = main_cte.sequence_id + 1))
)
SELECT
*
FROM
main_cte
ORDER BY
Category,
bucket,
sequence_id
答案 3 :(得分：1)
DECLARE @Detail table (DetailID int primary key, Category char(4), Number int)
SET NOCOUNT ON
INSERT @Detail VALUES ( 1, 'AAAA',100)
INSERT @Detail VALUES ( 2, 'AAAA', 50)
INSERT @Detail VALUES ( 3, 'AAAA',300)
INSERT @Detail VALUES ( 4, 'AAAA',200)
INSERT @Detail VALUES ( 5, 'BBBB',500)
INSERT @Detail VALUES ( 6, 'CCCC',200)
INSERT @Detail VALUES ( 7, 'CCCC',100)
INSERT @Detail VALUES ( 8, 'CCCC', 50)
INSERT @Detail VALUES ( 9, 'DDDD',800)
INSERT @Detail VALUES (10, 'EEEE',100)
INSERT @Detail VALUES (11, 'AAAA',200) --EDIT added
INSERT @Detail VALUES (12, 'AAAA',200) --EDIT added
INSERT @Detail VALUES (13, 'AAAA',200) --EDIT added
INSERT @Detail VALUES (14, 'AAAA',200) --EDIT added
SET NOCOUNT OFF
DECLARE @Limit int
SET @Limit=500
DECLARE @DetailTemp table (PID INT IDENTITY(1,1), DetailID int primary key, Category char(4), Number int)
DECLARE @DetailFinal table (DetailID int, Category char(4), Number int)
DECLARE @DetailCount int
SET @DetailCount = 0;
INSERT @DetailTemp
SELECT DetailId, Category, Number FROM @Detail ORDER BY Category, DetailId
SELECT @DetailCount = @@ROWCOUNT
DECLARE @CurrentPid int
SET @CurrentPid = 1
DECLARE @ThisId int
DECLARE @ThisCategory char(4)
DECLARE @ThisNumber int
DECLARE @CurrentCategory char(4)
DECLARE @CurrentSum INT
DECLARE @CurrentBucket INT
WHILE @CurrentPid <= @DetailCount
BEGIN
SELECT @ThisId = DetailId, @ThisCategory = Category, @ThisNumber = Number
FROM @DetailTemp
WHERE PID = @CurrentPid
IF @ThisCategory = @CurrentCategory
BEGIN
IF @CurrentSum + @ThisNumber > @Limit
BEGIN
SET @CurrentBucket = @CurrentBucket + 1
SET @CurrentSum = @ThisNumber
END
ELSE
BEGIN
SET @CurrentSum = @CurrentSum + @ThisNumber
END
END
ELSE
BEGIN
SET @CurrentBucket = 1
SET @CurrentCategory = @ThisCategory
SET @CurrentSum = @ThisNumber
END
WHILE @CurrentSum > @Limit
BEGIN
INSERT @DetailFinal SELECT @ThisId, @CurrentCategory, @CurrentBucket
SET @CurrentBucket = @CurrentBucket + 1
SET @CurrentSum = @CurrentSum - @Limit
END
INSERT @DetailFinal SELECT @ThisId, @CurrentCategory, @CurrentBucket
SET @CurrentPid = @CurrentPid + 1
END
SELECT * from @DetailFinal