我的问题与
有些相似Group by every N records in T-SQL
但是我想按最高金额分组
所以我有20条记录，总共amount为50,000，我需要将它们分组，以便每组最多可达10,000个。
我尝试使用一个运行值，给记录一个排名，然后将值＆lt; =当前排名相加，然后使用Floor((RunningValue - amount) / 10000)将它们分成子组，但有些情况下它会超过10,000最大值
示例数据，您可以在此处看到SubGroup 1超过10,000
SubGroupNo RowNo amount RunningValue
0 1 790.5 790.5
0 2 790.5 1581
0 3 790.5 2371.5
0 4 790.5 3162
0 5 744 3906
0 6 744 4650
0 7 1348.5 5998.5
0 8 1348.5 7347
0 9 1348.5 8695.5
1 10 1348.5 10044
1 11 1302 11346
1 12 1302 12648
1 13 1302 13950
1 14 1302 15252
1 15 1255.5 16507.5
1 16 1209 17716.5
1 17 1116 18832.5
1 18 1116 19948.5
2 19 1302 21250.5
2 20 1302 22552.5
2 21 1302 23854.5
2 22 1255.5 25110
2 23 1255.5 26365.5
2 24 976.5 27342
答案 0 :(得分：2)
这可能不是最好的方法，但它有效。它假定您的RowNo是连续的。如果没有，我会在此解决方案中添加ROW_NUMBER()。
DECLARE @runningTotal decimal(7,2), @sgn tinyint, @cursor int, @count int
SET @runningTotal = '0.00'
SET @sgn = 0
SET @cursor = 1
SELECT @count = COUNT(*) FROM tbl
WHILE @cursor <= @count
BEGIN
SELECT @runningTotal = @runningTotal + amount FROM tbl WHERE RowNo = @cursor
IF @runningTotal > 10000
BEGIN
SELECT @runningTotal = amount FROM dbo.tbl WHERE RowNo = @cursor
SET @sgn = @sgn + 1
END
UPDATE tbl SET SubGroupNo = @sgn WHERE RowNo = @cursor
SET @cursor = @cursor + 1
END
SET NOCOUNT ON;
DECLARE @SubGroupNo tinyint, @RowNo smallint,
@amount decimal(8,2), @RunningTotal decimal(7,2)
SET @SubGroupNo = 0
SET @RunningTotal = '0.00'
DECLARE row_cursor CURSOR FOR
SELECT RowNo, amount FROM dbo.tbl
OPEN row_cursor
FETCH NEXT FROM row_cursor
INTO @RowNo, @amount
WHILE @@FETCH_STATUS = 0
BEGIN
SET @RunningTotal = @RunningTotal + @amount
IF @RunningTotal > 10000
BEGIN
SET @RunningTotal = @amount
SET @SubGroupNo = @SubGroupNo + 1
END
PRINT @RowNo
PRINT @RunningTotal
PRINT @SubGroupNo
UPDATE dbo.tbl SET SubGroupNo = @SubGroupNo WHERE RowNo = @RowNo
FETCH NEXT FROM row_cursor
INTO @RowNo, @amount
END
CLOSE row_cursor
DEALLOCATE row_cursor
结果
| SUBGROUPNO | ROWNO | AMOUNT | RUNNINGVALUE | ---------------------------------------------- | 0 | 1 | 790.5 | 790.5 | | 0 | 2 | 790.5 | 1581 | | 0 | 3 | 790.5 | 2371.5 | | 0 | 4 | 790.5 | 3162 | | 0 | 5 | 744 | 3906 | | 0 | 6 | 744 | 4650 | | 0 | 7 | 1348.5 | 5998.5 | | 0 | 8 | 1348.5 | 7347 | | 0 | 9 | 1348.5 | 8695.5 | | 1 | 10 | 1348.5 | 10044 | | 1 | 11 | 1302 | 11346 | | 1 | 12 | 1302 | 12648 | | 1 | 13 | 1302 | 13950 | | 1 | 14 | 1302 | 15252 | | 1 | 15 | 1255.5 | 16507.5 | | 1 | 16 | 1209 | 17716.5 | | 2 | 17 | 1116 | 18832.5 | | 2 | 18 | 1116 | 19948.5 | | 2 | 19 | 1302 | 21250.5 | | 2 | 20 | 1302 | 22552.5 | | 2 | 21 | 1302 | 23854.5 | | 2 | 22 | 1255.5 | 25110 | | 2 | 23 | 1255.5 | 26365.5 | | 2 | 24 | 976.5 | 27342 |
模式
CREATE TABLE tbl (
SubGroupNo tinyint,
RowNo tinyint PRIMARY KEY,
amount decimal(6,2),
RunningValue decimal(7,2))
INSERT INTO tbl (RowNo, amount, RunningValue)
VALUES
(1, '790.5', '790.5'),
(2, '790.5', '1581'),
(3, '790.5', '2371.5'),
(4, '790.5', '3162'),
(5, '744', '3906'),
(6, '744', '4650'),
(7, '1348.5', '5998.5'),
(8, '1348.5', '7347'),
(9, '1348.5', '8695.5'),
(10, '1348.5', '10044'),
(11, '1302', '11346'),
(12, '1302', '12648'),
(13, '1302', '13950'),
(14, '1302', '15252'),
(15, '1255.5', '16507.5'),
(16, '1209', '17716.5'),
(17, '1116', '18832.5'),
(18, '1116', '19948.5'),
(19, '1302', '21250.5'),
(20, '1302', '22552.5'),
(21, '1302', '23854.5'),
(22, '1255.5', '25110'),
(23, '1255.5', '26365.5'),
(24, '976.5', '27342')