SQL Server：將加權值分組到組

我有一個問題，我希望有一個簡單的解決方案，但是，我的頭撞到了一堵磚牆。我有一個包含一個表：SQL Server：將加權值分組到組

項目ID
項目值
集團

我曾希望是所有項目分成組，其中ItemValues的一組中的總和爲大致相等。到目前爲止，我用ntile等的努力產生了非常不平衡的羣體。這是使用SQL Server 2008 R2（10.50.6220）。

非常感謝任何幫助。

代碼來創建表：

------------------------------ 
--Table structure for [TstGroupWeight] 
------------------------------ 
DROP TABLE [TstGroupWeight] 
GO 
CREATE TABLE [TstGroupWeight] 
(
    [ItemID] int NOT NULL PRIMARY KEY , 
    [ItemValue] int NULL , 
    [Group] int NULL 
) 
GO 

-- ---------------------------- 
-- Records of TstGroupWeight 
-- ---------------------------- 
BEGIN TRANSACTION 
GO 
INSERT INTO [TstGroupWeight] VALUES (N'1', N'36', null); 
INSERT INTO [TstGroupWeight] VALUES (N'2', N'5', null); 
INSERT INTO [TstGroupWeight] VALUES (N'3', N'37', null); 
INSERT INTO [TstGroupWeight] VALUES (N'4', N'11', null); 
INSERT INTO [TstGroupWeight] VALUES (N'5', N'1', null); 
INSERT INTO [TstGroupWeight] VALUES (N'6', N'16', null); 
INSERT INTO [TstGroupWeight] VALUES (N'7', N'18', null); 
INSERT INTO [TstGroupWeight] VALUES (N'8', N'14', null); 
INSERT INTO [TstGroupWeight] VALUES (N'9', N'9', null); 
INSERT INTO [TstGroupWeight] VALUES (N'10', N'4', null); 
INSERT INTO [TstGroupWeight] VALUES (N'11', N'35', null); 
INSERT INTO [TstGroupWeight] VALUES (N'12', N'37', null); 
INSERT INTO [TstGroupWeight] VALUES (N'13', N'36', null); 
INSERT INTO [TstGroupWeight] VALUES (N'14', N'36', null); 
INSERT INTO [TstGroupWeight] VALUES (N'15', N'5', null); 
INSERT INTO [TstGroupWeight] VALUES (N'16', N'37', null); 
INSERT INTO [TstGroupWeight] VALUES (N'17', N'26', null); 
INSERT INTO [TstGroupWeight] VALUES (N'18', N'12', null); 
INSERT INTO [TstGroupWeight] VALUES (N'19', N'21', null); 
INSERT INTO [TstGroupWeight] VALUES (N'20', N'10', null); 
INSERT INTO [TstGroupWeight] VALUES (N'21', N'6', null); 
INSERT INTO [TstGroupWeight] VALUES (N'22', N'27', null); 
INSERT INTO [TstGroupWeight] VALUES (N'23', N'11', null); 
INSERT INTO [TstGroupWeight] VALUES (N'24', N'5', null); 
INSERT INTO [TstGroupWeight] VALUES (N'25', N'15', null); 
INSERT INTO [TstGroupWeight] VALUES (N'26', N'29', null); 
INSERT INTO [TstGroupWeight] VALUES (N'27', N'42', null); 
INSERT INTO [TstGroupWeight] VALUES (N'28', N'11', null); 
INSERT INTO [TstGroupWeight] VALUES (N'29', N'27', null); 
INSERT INTO [TstGroupWeight] VALUES (N'30', N'34', null); 
INSERT INTO [TstGroupWeight] VALUES (N'31', N'33', null); 
INSERT INTO [TstGroupWeight] VALUES (N'32', N'11', null); 
INSERT INTO [TstGroupWeight] VALUES (N'33', N'40', null); 
INSERT INTO [TstGroupWeight] VALUES (N'34', N'29', null); 
INSERT INTO [TstGroupWeight] VALUES (N'35', N'15', null); 
INSERT INTO [TstGroupWeight] VALUES (N'36', N'9', null); 
INSERT INTO [TstGroupWeight] VALUES (N'37', N'28', null); 
INSERT INTO [TstGroupWeight] VALUES (N'38', N'19', null); 
INSERT INTO [TstGroupWeight] VALUES (N'39', N'12', null); 
INSERT INTO [TstGroupWeight] VALUES (N'40', N'27', null); 
INSERT INTO [TstGroupWeight] VALUES (N'41', N'13', null); 
INSERT INTO [TstGroupWeight] VALUES (N'42', N'22', null); 
INSERT INTO [TstGroupWeight] VALUES (N'43', N'7', null); 
INSERT INTO [TstGroupWeight] VALUES (N'44', N'8', null); 
INSERT INTO [TstGroupWeight] VALUES (N'45', N'34', null); 
INSERT INTO [TstGroupWeight] VALUES (N'46', N'9', null); 
INSERT INTO [TstGroupWeight] VALUES (N'47', N'19', null); 
INSERT INTO [TstGroupWeight] VALUES (N'48', N'21', null); 
INSERT INTO [TstGroupWeight] VALUES (N'49', N'41', null); 
INSERT INTO [TstGroupWeight] VALUES (N'50', N'32', null); 
INSERT INTO [TstGroupWeight] VALUES (N'51', N'34', null); 
INSERT INTO [TstGroupWeight] VALUES (N'52', N'28', null); 
INSERT INTO [TstGroupWeight] VALUES (N'53', N'41', null); 
INSERT INTO [TstGroupWeight] VALUES (N'54', N'18', null); 
INSERT INTO [TstGroupWeight] VALUES (N'55', N'33', null); 
INSERT INTO [TstGroupWeight] VALUES (N'56', N'40', null); 
INSERT INTO [TstGroupWeight] VALUES (N'57', N'19', null); 
INSERT INTO [TstGroupWeight] VALUES (N'58', N'42', null); 
INSERT INTO [TstGroupWeight] VALUES (N'59', N'12', null); 
INSERT INTO [TstGroupWeight] VALUES (N'60', N'4', null); 
INSERT INTO [TstGroupWeight] VALUES (N'61', N'38', null); 
INSERT INTO [TstGroupWeight] VALUES (N'62', N'5', null); 
INSERT INTO [TstGroupWeight] VALUES (N'63', N'37', null); 
INSERT INTO [TstGroupWeight] VALUES (N'64', N'36', null); 
INSERT INTO [TstGroupWeight] VALUES (N'65', N'13', null); 
INSERT INTO [TstGroupWeight] VALUES (N'66', N'15', null); 
INSERT INTO [TstGroupWeight] VALUES (N'67', N'5', null); 
INSERT INTO [TstGroupWeight] VALUES (N'68', N'4', null); 
INSERT INTO [TstGroupWeight] VALUES (N'69', N'4', null); 
INSERT INTO [TstGroupWeight] VALUES (N'70', N'7', null); 
INSERT INTO [TstGroupWeight] VALUES (N'71', N'1', null); 
INSERT INTO [TstGroupWeight] VALUES (N'72', N'21', null); 
INSERT INTO [TstGroupWeight] VALUES (N'73', N'13', null); 
INSERT INTO [TstGroupWeight] VALUES (N'74', N'22', null); 
INSERT INTO [TstGroupWeight] VALUES (N'75', N'20', null); 
INSERT INTO [TstGroupWeight] VALUES (N'76', N'1', null); 
INSERT INTO [TstGroupWeight] VALUES (N'77', N'38', null); 
INSERT INTO [TstGroupWeight] VALUES (N'78', N'39', null); 
INSERT INTO [TstGroupWeight] VALUES (N'79', N'5', null); 
INSERT INTO [TstGroupWeight] VALUES (N'80', N'33', null); 
INSERT INTO [TstGroupWeight] VALUES (N'81', N'0', null); 
INSERT INTO [TstGroupWeight] VALUES (N'82', N'9', null); 
INSERT INTO [TstGroupWeight] VALUES (N'83', N'24', null); 
INSERT INTO [TstGroupWeight] VALUES (N'84', N'36', null); 
INSERT INTO [TstGroupWeight] VALUES (N'85', N'29', null); 
INSERT INTO [TstGroupWeight] VALUES (N'86', N'26', null); 
INSERT INTO [TstGroupWeight] VALUES (N'87', N'6', null); 
INSERT INTO [TstGroupWeight] VALUES (N'88', N'37', null); 
INSERT INTO [TstGroupWeight] VALUES (N'89', N'37', null); 
INSERT INTO [TstGroupWeight] VALUES (N'90', N'19', null); 
INSERT INTO [TstGroupWeight] VALUES (N'91', N'4', null); 
INSERT INTO [TstGroupWeight] VALUES (N'92', N'25', null); 
INSERT INTO [TstGroupWeight] VALUES (N'93', N'5', null); 
INSERT INTO [TstGroupWeight] VALUES (N'94', N'5', null); 
INSERT INTO [TstGroupWeight] VALUES (N'95', N'28', null); 
INSERT INTO [TstGroupWeight] VALUES (N'96', N'16', null); 
INSERT INTO [TstGroupWeight] VALUES (N'97', N'2', null); 
INSERT INTO [TstGroupWeight] VALUES (N'98', N'11', null); 
INSERT INTO [TstGroupWeight] VALUES (N'99', N'25', null); 
INSERT INTO [TstGroupWeight] VALUES (N'100', N'14', null); 
GO 
INSERT INTO [TstGroupWeight] VALUES (N'101', N'14', null); 
INSERT INTO [TstGroupWeight] VALUES (N'102', N'2', null); 
INSERT INTO [TstGroupWeight] VALUES (N'103', N'5', null); 
INSERT INTO [TstGroupWeight] VALUES (N'104', N'12', null); 
INSERT INTO [TstGroupWeight] VALUES (N'105', N'35', null); 
INSERT INTO [TstGroupWeight] VALUES (N'106', N'37', null); 
INSERT INTO [TstGroupWeight] VALUES (N'107', N'0', null); 
INSERT INTO [TstGroupWeight] VALUES (N'108', N'21', null); 
INSERT INTO [TstGroupWeight] VALUES (N'109', N'38', null); 
INSERT INTO [TstGroupWeight] VALUES (N'110', N'39', null); 
INSERT INTO [TstGroupWeight] VALUES (N'111', N'11', null); 
INSERT INTO [TstGroupWeight] VALUES (N'112', N'38', null); 
INSERT INTO [TstGroupWeight] VALUES (N'113', N'25', null); 
INSERT INTO [TstGroupWeight] VALUES (N'114', N'5', null); 
INSERT INTO [TstGroupWeight] VALUES (N'115', N'3', null); 
INSERT INTO [TstGroupWeight] VALUES (N'116', N'26', null); 
INSERT INTO [TstGroupWeight] VALUES (N'117', N'38', null); 
INSERT INTO [TstGroupWeight] VALUES (N'118', N'3', null); 
INSERT INTO [TstGroupWeight] VALUES (N'119', N'15', null); 
INSERT INTO [TstGroupWeight] VALUES (N'120', N'0', null); 
INSERT INTO [TstGroupWeight] VALUES (N'121', N'14', null); 
INSERT INTO [TstGroupWeight] VALUES (N'122', N'2', null); 
INSERT INTO [TstGroupWeight] VALUES (N'123', N'6', null); 
INSERT INTO [TstGroupWeight] VALUES (N'124', N'6', null); 
INSERT INTO [TstGroupWeight] VALUES (N'125', N'14', null); 
INSERT INTO [TstGroupWeight] VALUES (N'126', N'34', null); 
INSERT INTO [TstGroupWeight] VALUES (N'127', N'21', null); 
INSERT INTO [TstGroupWeight] VALUES (N'128', N'21', null); 
INSERT INTO [TstGroupWeight] VALUES (N'129', N'31', null); 
INSERT INTO [TstGroupWeight] VALUES (N'130', N'26', null); 
INSERT INTO [TstGroupWeight] VALUES (N'131', N'2', null); 
INSERT INTO [TstGroupWeight] VALUES (N'132', N'38', null); 
INSERT INTO [TstGroupWeight] VALUES (N'133', N'40', null); 
INSERT INTO [TstGroupWeight] VALUES (N'134', N'30', null); 
INSERT INTO [TstGroupWeight] VALUES (N'135', N'13', null); 
INSERT INTO [TstGroupWeight] VALUES (N'136', N'12', null); 
INSERT INTO [TstGroupWeight] VALUES (N'137', N'14', null); 
INSERT INTO [TstGroupWeight] VALUES (N'138', N'31', null); 
INSERT INTO [TstGroupWeight] VALUES (N'139', N'27', null); 
INSERT INTO [TstGroupWeight] VALUES (N'140', N'9', null); 
INSERT INTO [TstGroupWeight] VALUES (N'141', N'21', null); 
INSERT INTO [TstGroupWeight] VALUES (N'142', N'10', null); 
INSERT INTO [TstGroupWeight] VALUES (N'143', N'36', null); 
INSERT INTO [TstGroupWeight] VALUES (N'144', N'32', null); 
INSERT INTO [TstGroupWeight] VALUES (N'145', N'38', null); 
INSERT INTO [TstGroupWeight] VALUES (N'146', N'14', null); 
INSERT INTO [TstGroupWeight] VALUES (N'147', N'2', null); 
INSERT INTO [TstGroupWeight] VALUES (N'148', N'17', null); 
INSERT INTO [TstGroupWeight] VALUES (N'149', N'34', null); 
INSERT INTO [TstGroupWeight] VALUES (N'150', N'41', null); 
INSERT INTO [TstGroupWeight] VALUES (N'151', N'35', null); 
INSERT INTO [TstGroupWeight] VALUES (N'152', N'12', null); 
INSERT INTO [TstGroupWeight] VALUES (N'153', N'23', null); 
INSERT INTO [TstGroupWeight] VALUES (N'154', N'28', null); 
INSERT INTO [TstGroupWeight] VALUES (N'155', N'32', null); 
INSERT INTO [TstGroupWeight] VALUES (N'156', N'25', null); 
INSERT INTO [TstGroupWeight] VALUES (N'157', N'17', null); 
INSERT INTO [TstGroupWeight] VALUES (N'158', N'1', null); 
INSERT INTO [TstGroupWeight] VALUES (N'159', N'42', null); 
INSERT INTO [TstGroupWeight] VALUES (N'160', N'38', null); 
INSERT INTO [TstGroupWeight] VALUES (N'161', N'29', null); 
INSERT INTO [TstGroupWeight] VALUES (N'162', N'23', null); 
INSERT INTO [TstGroupWeight] VALUES (N'163', N'6', null); 
INSERT INTO [TstGroupWeight] VALUES (N'164', N'32', null); 
INSERT INTO [TstGroupWeight] VALUES (N'165', N'14', null); 
INSERT INTO [TstGroupWeight] VALUES (N'166', N'27', null); 
INSERT INTO [TstGroupWeight] VALUES (N'167', N'4', null); 
INSERT INTO [TstGroupWeight] VALUES (N'168', N'29', null); 
INSERT INTO [TstGroupWeight] VALUES (N'169', N'16', null); 
INSERT INTO [TstGroupWeight] VALUES (N'170', N'20', null); 
INSERT INTO [TstGroupWeight] VALUES (N'171', N'35', null); 
INSERT INTO [TstGroupWeight] VALUES (N'172', N'2', null); 
INSERT INTO [TstGroupWeight] VALUES (N'173', N'37', null); 
INSERT INTO [TstGroupWeight] VALUES (N'174', N'26', null); 
INSERT INTO [TstGroupWeight] VALUES (N'175', N'22', null); 
INSERT INTO [TstGroupWeight] VALUES (N'176', N'34', null); 
INSERT INTO [TstGroupWeight] VALUES (N'177', N'0', null); 
INSERT INTO [TstGroupWeight] VALUES (N'178', N'30', null); 
INSERT INTO [TstGroupWeight] VALUES (N'179', N'41', null); 
INSERT INTO [TstGroupWeight] VALUES (N'180', N'30', null); 
INSERT INTO [TstGroupWeight] VALUES (N'181', N'41', null); 
INSERT INTO [TstGroupWeight] VALUES (N'182', N'31', null); 
INSERT INTO [TstGroupWeight] VALUES (N'183', N'13', null); 
INSERT INTO [TstGroupWeight] VALUES (N'184', N'42', null); 
INSERT INTO [TstGroupWeight] VALUES (N'185', N'41', null); 
INSERT INTO [TstGroupWeight] VALUES (N'186', N'37', null); 
INSERT INTO [TstGroupWeight] VALUES (N'187', N'29', null); 
INSERT INTO [TstGroupWeight] VALUES (N'188', N'7', null); 
INSERT INTO [TstGroupWeight] VALUES (N'189', N'5', null); 
INSERT INTO [TstGroupWeight] VALUES (N'190', N'9', null); 
INSERT INTO [TstGroupWeight] VALUES (N'191', N'18', null); 
INSERT INTO [TstGroupWeight] VALUES (N'192', N'16', null); 
INSERT INTO [TstGroupWeight] VALUES (N'193', N'29', null); 
INSERT INTO [TstGroupWeight] VALUES (N'194', N'16', null); 
INSERT INTO [TstGroupWeight] VALUES (N'195', N'18', null); 
INSERT INTO [TstGroupWeight] VALUES (N'196', N'18', null); 
INSERT INTO [TstGroupWeight] VALUES (N'197', N'14', null); 
INSERT INTO [TstGroupWeight] VALUES (N'198', N'0', null); 
INSERT INTO [TstGroupWeight] VALUES (N'199', N'35', null); 
INSERT INTO [TstGroupWeight] VALUES (N'200', N'20', null); 
GO 
INSERT INTO [TstGroupWeight] VALUES (N'201', N'34', null); 
INSERT INTO [TstGroupWeight] VALUES (N'202', N'35', null); 
INSERT INTO [TstGroupWeight] VALUES (N'203', N'6', null); 
INSERT INTO [TstGroupWeight] VALUES (N'204', N'42', null); 
INSERT INTO [TstGroupWeight] VALUES (N'205', N'18', null); 
INSERT INTO [TstGroupWeight] VALUES (N'206', N'31', null); 
INSERT INTO [TstGroupWeight] VALUES (N'207', N'4', null); 
INSERT INTO [TstGroupWeight] VALUES (N'208', N'9', null); 
INSERT INTO [TstGroupWeight] VALUES (N'209', N'18', null); 
INSERT INTO [TstGroupWeight] VALUES (N'210', N'14', null); 
INSERT INTO [TstGroupWeight] VALUES (N'211', N'28', null); 
INSERT INTO [TstGroupWeight] VALUES (N'212', N'38', null); 
INSERT INTO [TstGroupWeight] VALUES (N'213', N'38', null); 
INSERT INTO [TstGroupWeight] VALUES (N'214', N'7', null); 
INSERT INTO [TstGroupWeight] VALUES (N'215', N'40', null); 
INSERT INTO [TstGroupWeight] VALUES (N'216', N'34', null); 
INSERT INTO [TstGroupWeight] VALUES (N'217', N'7', null); 
INSERT INTO [TstGroupWeight] VALUES (N'218', N'15', null); 
INSERT INTO [TstGroupWeight] VALUES (N'219', N'27', null); 
INSERT INTO [TstGroupWeight] VALUES (N'220', N'35', null); 
INSERT INTO [TstGroupWeight] VALUES (N'221', N'13', null); 
INSERT INTO [TstGroupWeight] VALUES (N'222', N'41', null); 
INSERT INTO [TstGroupWeight] VALUES (N'223', N'41', null); 
INSERT INTO [TstGroupWeight] VALUES (N'224', N'2', null); 
INSERT INTO [TstGroupWeight] VALUES (N'225', N'23', null); 
INSERT INTO [TstGroupWeight] VALUES (N'226', N'18', null); 
INSERT INTO [TstGroupWeight] VALUES (N'227', N'39', null); 
INSERT INTO [TstGroupWeight] VALUES (N'228', N'28', null); 
INSERT INTO [TstGroupWeight] VALUES (N'229', N'27', null); 
INSERT INTO [TstGroupWeight] VALUES (N'230', N'8', null); 
INSERT INTO [TstGroupWeight] VALUES (N'231', N'26', null); 
INSERT INTO [TstGroupWeight] VALUES (N'232', N'11', null); 
INSERT INTO [TstGroupWeight] VALUES (N'233', N'23', null); 
INSERT INTO [TstGroupWeight] VALUES (N'234', N'13', null); 
INSERT INTO [TstGroupWeight] VALUES (N'235', N'40', null); 
INSERT INTO [TstGroupWeight] VALUES (N'236', N'0', null); 
INSERT INTO [TstGroupWeight] VALUES (N'237', N'24', null); 
INSERT INTO [TstGroupWeight] VALUES (N'238', N'24', null); 
INSERT INTO [TstGroupWeight] VALUES (N'239', N'22', null); 
INSERT INTO [TstGroupWeight] VALUES (N'240', N'20', null); 
INSERT INTO [TstGroupWeight] VALUES (N'241', N'39', null); 
INSERT INTO [TstGroupWeight] VALUES (N'242', N'2', null); 
INSERT INTO [TstGroupWeight] VALUES (N'243', N'42', null); 
INSERT INTO [TstGroupWeight] VALUES (N'244', N'7', null); 
INSERT INTO [TstGroupWeight] VALUES (N'245', N'27', null); 
INSERT INTO [TstGroupWeight] VALUES (N'246', N'8', null); 
INSERT INTO [TstGroupWeight] VALUES (N'247', N'7', null); 
INSERT INTO [TstGroupWeight] VALUES (N'248', N'19', null); 
INSERT INTO [TstGroupWeight] VALUES (N'249', N'21', null); 
INSERT INTO [TstGroupWeight] VALUES (N'250', N'35', null); 
INSERT INTO [TstGroupWeight] VALUES (N'251', N'11', null); 
INSERT INTO [TstGroupWeight] VALUES (N'252', N'30', null); 
INSERT INTO [TstGroupWeight] VALUES (N'253', N'19', null); 
INSERT INTO [TstGroupWeight] VALUES (N'254', N'18', null); 
INSERT INTO [TstGroupWeight] VALUES (N'255', N'14', null); 
INSERT INTO [TstGroupWeight] VALUES (N'256', N'28', null); 
INSERT INTO [TstGroupWeight] VALUES (N'257', N'9', null); 
INSERT INTO [TstGroupWeight] VALUES (N'258', N'4', null); 
INSERT INTO [TstGroupWeight] VALUES (N'259', N'10', null); 
INSERT INTO [TstGroupWeight] VALUES (N'260', N'26', null); 
INSERT INTO [TstGroupWeight] VALUES (N'261', N'12', null); 
INSERT INTO [TstGroupWeight] VALUES (N'262', N'0', null); 
INSERT INTO [TstGroupWeight] VALUES (N'263', N'39', null); 
INSERT INTO [TstGroupWeight] VALUES (N'264', N'35', null); 
INSERT INTO [TstGroupWeight] VALUES (N'265', N'12', null); 
INSERT INTO [TstGroupWeight] VALUES (N'266', N'6', null); 
INSERT INTO [TstGroupWeight] VALUES (N'267', N'2', null); 
INSERT INTO [TstGroupWeight] VALUES (N'268', N'24', null); 
INSERT INTO [TstGroupWeight] VALUES (N'269', N'34', null); 
INSERT INTO [TstGroupWeight] VALUES (N'270', N'10', null); 
INSERT INTO [TstGroupWeight] VALUES (N'271', N'13', null); 
INSERT INTO [TstGroupWeight] VALUES (N'272', N'16', null); 
INSERT INTO [TstGroupWeight] VALUES (N'273', N'16', null); 
INSERT INTO [TstGroupWeight] VALUES (N'274', N'3', null); 
INSERT INTO [TstGroupWeight] VALUES (N'275', N'3', null); 
INSERT INTO [TstGroupWeight] VALUES (N'276', N'26', null); 
INSERT INTO [TstGroupWeight] VALUES (N'277', N'4', null); 
INSERT INTO [TstGroupWeight] VALUES (N'278', N'23', null); 
INSERT INTO [TstGroupWeight] VALUES (N'279', N'4', null); 
INSERT INTO [TstGroupWeight] VALUES (N'280', N'34', null); 
INSERT INTO [TstGroupWeight] VALUES (N'281', N'23', null); 
INSERT INTO [TstGroupWeight] VALUES (N'282', N'18', null); 
INSERT INTO [TstGroupWeight] VALUES (N'283', N'17', null); 
INSERT INTO [TstGroupWeight] VALUES (N'284', N'25', null); 
INSERT INTO [TstGroupWeight] VALUES (N'285', N'32', null); 
INSERT INTO [TstGroupWeight] VALUES (N'286', N'24', null); 
INSERT INTO [TstGroupWeight] VALUES (N'287', N'37', null); 
INSERT INTO [TstGroupWeight] VALUES (N'288', N'38', null); 
INSERT INTO [TstGroupWeight] VALUES (N'289', N'18', null); 
INSERT INTO [TstGroupWeight] VALUES (N'290', N'40', null); 
INSERT INTO [TstGroupWeight] VALUES (N'291', N'12', null); 
INSERT INTO [TstGroupWeight] VALUES (N'292', N'9', null); 
INSERT INTO [TstGroupWeight] VALUES (N'293', N'9', null); 
INSERT INTO [TstGroupWeight] VALUES (N'294', N'32', null); 
INSERT INTO [TstGroupWeight] VALUES (N'295', N'11', null); 
INSERT INTO [TstGroupWeight] VALUES (N'296', N'23', null); 
INSERT INTO [TstGroupWeight] VALUES (N'297', N'25', null); 
INSERT INTO [TstGroupWeight] VALUES (N'298', N'30', null); 
INSERT INTO [TstGroupWeight] VALUES (N'299', N'24', null); 
INSERT INTO [TstGroupWeight] VALUES (N'300', N'6', null); 
GO 
COMMIT TRANSACTION 
GO

來源

2016-01-29 Ads

http://stackoverflow.com/questions/17889830/create-evenly-sized-groups-based-on-aggregate – Mihai

這是裝箱問題和一般的解決方案可能是用於SQL太難了。一種在實踐中工作得很好的方法是枚舉組，然後爲每個組取第n個值。所以，如果你想要三組：

select t.*, (seqnum % 3) as grp 
from (select t.*, 
      row_number() over (order by itemvalue) as seqnum 
     from t 
    ) t;

這適用於值小於相當密集的範圍內（以及在其他情況下）。當有少量異常值時它不起作用。

來源

2016-01-29 22:17:49

假設您想要基於按ItemID排序的數據創建這些組，您的NTILE將失敗，因爲它會創建具有相同行數但不相同總數的組。您只需要基於值的累積和來應用分位數邏輯。

計算ñ位數是非常相似的：

n * (RANK() OVER (ORDER BY ItemID) - 1) 
    /COUNT(*) OVER()

現在改變計數SUM：

(n * sum(ItemValue) over (order by ItemID rows unbounded preceding) - 1) 
    /sum(ItemValue) over()

的SQL Server 2008不支持累計總和，所以你需要使用相關子查詢（性能可能不好）。

with cte as 
(
    select ItemID, ItemValue, 

    -- sum of all values 
     sum(ItemValue) over() as all_sum, 

    -- cumulative sum 
     (select sum(ItemValue) 
     from TstGroupWeight as t2 
     where t2.ItemID <= t1.ItemID) as cum_sum 

    -- much easier in SQL Server 2012 
    -- sum(ItemValue) 
    -- over (order by ItemID 
    --   rows unbounded preceding) as cum_sum 
    from TstGroupWeight as t1 
) 
select ItemID, ItemValue, cum_sum, 
    -- n = number of quantiles 
    (n * cum_sum-1)/all_sum as grp 
from cte

參見fiddle

當然相同的邏輯可使用遞歸（或光標）被應用，但根據實際的行號的所有版本可能運行緩慢。

來源

2016-01-29 23:34:57 dnoeth

SQL Server：將加權值分組到組

回答

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