SQL 2012 中游标的有效替代方案，用于获取付款计划计算的最后一个值答案

【问题标题】：Efficient alternate to the cursor in TSQL 2012 to get last value for payment schedule calculationSQL 2012 中游标的有效替代方案，用于获取付款计划计算的最后一个值
【发布时间】：2023-04-01 21:19:02
【问题描述】：

我正在尝试制定年金支付计划。我知道网上有一些可用的解决方案，但由于我需要更改每月付款金额，我无法使用这些解决方案，并且由于安全策略，我也无法安装新软件包。现在我正在努力计算每月的期初余额，因为它取决于最后一行计算的资本。有没有比光标更有效的方法来做到这一点。我现在有大约 3000 万行。

我拥有的数据：

这是一个非常简单的示例，可能有不同的费率、不同的每月付款和缺少的日期。所以我无法使用在线可用的解决方案。

我想要的最终结果：

地点：

利息 = 期初余额 x 利率费用
资本 = 每月还款 - 利息
期初余额 = 最后期初余额 - 最后资本

我尝试使用LAG，但它不起作用，因为LAG 是一个确定性函数。

这是帐户数据的脚本。

CREATE TABLE [temp_da_test].[example_3](
    [Account] [nvarchar](255) NULL,
    [Month] [date] NULL,
    [Rate Charge] [float] NULL,
    [Opening Balance] [money] NULL,
    [Monthly Repayment] [money] NULL,
    [Interest] [money] NULL,
    [Capital] [money] NULL
) ON [PRIMARY]

GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'A', CAST(N'2005-06-30' AS Date), 0.014419, 2000.0000, 0.0000, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'A', CAST(N'2005-07-31' AS Date), 0.0149, NULL, 35.8800, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'A', CAST(N'2005-08-31' AS Date), 0.0149, NULL, 35.8800, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'A', CAST(N'2005-09-30' AS Date), 0.014419, NULL, 35.8800, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'A', CAST(N'2005-10-31' AS Date), 0.0149, NULL, 35.8800, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'A', CAST(N'2005-11-30' AS Date), 0.014419, NULL, 35.8800, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'A', CAST(N'2005-12-31' AS Date), 0.0149, NULL, 35.8800, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'A', CAST(N'2006-01-31' AS Date), 0.0149, NULL, 35.8800, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'A', CAST(N'2006-02-28' AS Date), 0.013458, NULL, 35.8800, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'A', CAST(N'2006-03-31' AS Date), 0.0149, NULL, 35.8800, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'A', CAST(N'2006-04-30' AS Date), 0.014419, NULL, 35.8800, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'A', CAST(N'2006-05-31' AS Date), 0.0149, NULL, 35.8800, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'A', CAST(N'2006-06-30' AS Date), 0.014419, NULL, 35.8800, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'A', CAST(N'2006-07-31' AS Date), 0.0149, NULL, 35.8800, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'A', CAST(N'2006-08-31' AS Date), 0.0149, NULL, 35.8800, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'A', CAST(N'2006-09-30' AS Date), 0.014419, NULL, 35.8800, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'A', CAST(N'2006-10-31' AS Date), 0.0149, NULL, 35.8800, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'A', CAST(N'2006-11-30' AS Date), 0.014419, NULL, 35.8800, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'A', CAST(N'2006-12-31' AS Date), 0.0149, NULL, 35.8800, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'A', CAST(N'2007-01-31' AS Date), 0.0149, NULL, 35.8800, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'B', CAST(N'2005-06-30' AS Date), 0.014419, 4000.0000, 0.0000, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'B', CAST(N'2005-07-31' AS Date), 0.0149, NULL, 71.7600, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'B', CAST(N'2005-08-31' AS Date), 0.0149, NULL, 71.7600, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'B', CAST(N'2005-09-30' AS Date), 0.014419, NULL, 71.7600, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'B', CAST(N'2005-10-31' AS Date), 0.0149, NULL, 71.7600, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'B', CAST(N'2005-11-30' AS Date), 0.014419, NULL, 71.7600, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'B', CAST(N'2005-12-31' AS Date), 0.0149, NULL, 71.7600, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'B', CAST(N'2006-01-31' AS Date), 0.0149, NULL, 71.7600, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'B', CAST(N'2006-02-28' AS Date), 0.013458, NULL, 71.7600, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'B', CAST(N'2006-03-31' AS Date), 0.0149, NULL, 71.7600, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'B', CAST(N'2006-04-30' AS Date), 0.014419, NULL, 71.7600, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'B', CAST(N'2006-05-31' AS Date), 0.0149, NULL, 71.7600, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'B', CAST(N'2006-06-30' AS Date), 0.014419, NULL, 71.7600, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'B', CAST(N'2006-07-31' AS Date), 0.0149, NULL, 71.7600, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'B', CAST(N'2006-08-31' AS Date), 0.0149, NULL, 71.7600, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'B', CAST(N'2006-09-30' AS Date), 0.014419, NULL, 71.7600, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'B', CAST(N'2006-10-31' AS Date), 0.0149, NULL, 71.7600, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'B', CAST(N'2006-11-30' AS Date), 0.014419, NULL, 71.7600, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'B', CAST(N'2006-12-31' AS Date), 0.0149, NULL, 71.7600, NULL, NULL)
GO
INSERT [temp_da_test].[example_3] ([Account], [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]) VALUES (N'B', CAST(N'2007-01-31' AS Date), 0.0149, NULL, 71.7600, NULL, NULL)
GO

【问题讨论】：

标签： tsql cursor common-table-expression lag annuity

【解决方案1】：

由于您的利率不一致，因此您不能使用interest rate calculation，因此您不会比逐行更有效。

虽然在性能方面不是最好的，但您会看到使用递归 Common Table Expression (CTE) 的执行效率更高，joins 对其自身并检查派生表中的一行与下一行传入，在您的情况下，您需要计算下个月的值。

由于CTE 中已完全存在此行，因此您可以像在cursor 中一样引用计算值：

declare @t table(Account nvarchar(5),[Month] date null,[Rate Charge] float null,[Opening Balance] money null,[Monthly Repayment] money null);
insert into @t (Account, [Month], [Rate Charge], [Opening Balance], [Monthly Repayment]) values
 (N'A', CAST(N'2005-06-30' AS Date), 0.014419, 2000.0000, 0.0000),(N'A', CAST(N'2005-07-31' AS Date), 0.0149, NULL, 35.8800),(N'A', CAST(N'2005-08-31' AS Date), 0.0149, NULL, 35.8800),(N'A', CAST(N'2005-09-30' AS Date), 0.014419, NULL, 35.8800),(N'A', CAST(N'2005-10-31' AS Date), 0.0149, NULL, 35.8800),(N'A', CAST(N'2005-11-30' AS Date), 0.014419, NULL, 35.8800),(N'A', CAST(N'2005-12-31' AS Date), 0.0149, NULL, 35.8800),(N'A', CAST(N'2006-01-31' AS Date), 0.0149, NULL, 35.8800),(N'A', CAST(N'2006-02-28' AS Date), 0.013458, NULL, 35.8800),(N'A', CAST(N'2006-03-31' AS Date), 0.0149, NULL, 35.8800),(N'A', CAST(N'2006-04-30' AS Date), 0.014419, NULL, 35.8800),(N'A', CAST(N'2006-05-31' AS Date), 0.0149, NULL, 35.8800),(N'A', CAST(N'2006-06-30' AS Date), 0.014419, NULL, 35.8800),(N'A', CAST(N'2006-07-31' AS Date), 0.0149, NULL, 35.8800),(N'A', CAST(N'2006-08-31' AS Date), 0.0149, NULL, 35.8800),(N'A', CAST(N'2006-09-30' AS Date), 0.014419, NULL, 35.8800),(N'A', CAST(N'2006-10-31' AS Date), 0.0149, NULL, 35.8800),(N'A', CAST(N'2006-11-30' AS Date), 0.014419, NULL, 35.8800),(N'A', CAST(N'2006-12-31' AS Date), 0.0149, NULL, 35.8800),(N'A', CAST(N'2007-01-31' AS Date), 0.0149, NULL, 35.8800)
,(N'B', CAST(N'2005-06-30' AS Date), 0.014419, 4000.0000, 0.0000),(N'B', CAST(N'2005-07-31' AS Date), 0.0149, NULL, 71.7600),(N'B', CAST(N'2005-08-31' AS Date), 0.0149, NULL, 71.7600),(N'B', CAST(N'2005-09-30' AS Date), 0.014419, NULL, 71.7600),(N'B', CAST(N'2005-10-31' AS Date), 0.0149, NULL, 71.7600),(N'B', CAST(N'2005-11-30' AS Date), 0.014419, NULL, 71.7600),(N'B', CAST(N'2005-12-31' AS Date), 0.0149, NULL, 71.7600),(N'B', CAST(N'2006-01-31' AS Date), 0.0149, NULL, 71.7600),(N'B', CAST(N'2006-02-28' AS Date), 0.013458, NULL, 71.7600),(N'B', CAST(N'2006-03-31' AS Date), 0.0149, NULL, 71.7600),(N'B', CAST(N'2006-04-30' AS Date), 0.014419, NULL, 71.7600),(N'B', CAST(N'2006-05-31' AS Date), 0.0149, NULL, 71.7600),(N'B', CAST(N'2006-06-30' AS Date), 0.014419, NULL, 71.7600),(N'B', CAST(N'2006-07-31' AS Date), 0.0149, NULL, 71.7600),(N'B', CAST(N'2006-08-31' AS Date), 0.0149, NULL, 71.7600),(N'B', CAST(N'2006-09-30' AS Date), 0.014419, NULL, 71.7600),(N'B', CAST(N'2006-10-31' AS Date), 0.0149, NULL, 71.7600),(N'B', CAST(N'2006-11-30' AS Date), 0.014419, NULL, 71.7600),(N'B', CAST(N'2006-12-31' AS Date), 0.0149, NULL, 71.7600),(N'B', CAST(N'2007-01-31' AS Date), 0.0149, NULL, 71.7600)
;

with d as
(
    select Account
          ,[Month]
          ,[Rate Charge]
          ,[Opening Balance]
          ,[Monthly Repayment]
          ,row_number() over (order by Account,[Month]) as rn
    from @t
)
,c as
(
    -- Start with just the first row from your source data:
    select top 1 Account
                ,[Month]
                ,[Rate Charge]
                ,cast([Opening Balance] as decimal(12,2)) as [Opening Balance]
                ,[Monthly Repayment]
                ,[Opening Balance] * [Rate Charge] as Interest
                ,[Monthly Repayment] - ([Opening Balance] * [Rate Charge]) as Capital
                ,rn
    from d
    order by [Month]

    union all    -- Then add on the next row until the end of the dataset is reached:

    select d.Account
          ,d.[Month]
          ,d.[Rate Charge]
          ,case when c.Account <> d.Account     -- When we hit a new account, restart the calculations:
                then cast(d.[Opening Balance] as decimal(12,2))
                else cast(c.[Opening Balance] - c.Capital as decimal(12,2))
                end as [Opening Balance]
          ,d.[Monthly Repayment]
          ,case when c.Account <> d.Account
                then d.[Opening Balance] * d.[Rate Charge]
                else (c.[Opening Balance] - c.Capital) * d.[Rate Charge]
                end as Interest
          ,case when c.Account <> d.Account
                then d.[Monthly Repayment] - (d.[Opening Balance] * d.[Rate Charge])
                else d.[Monthly Repayment] - ((c.[Opening Balance] - c.Capital) * d.[Rate Charge])
                end as Capital
          ,d.rn
    from c
        join d
            on c.rn = d.rn-1
)
select Account
      ,[Month]
      ,[Rate Charge]
      ,[Opening Balance]
      ,[Monthly Repayment]
      ,Interest
      ,Capital
from c
order by rn
option (maxrecursion 0)    -- No matter how big the dataset is.

输出：

+---------+------------+-------------+-----------------+-------------------+------------------+------------------+
| Account |   Month    | Rate Charge | Opening Balance | Monthly Repayment |     Interest     |     Capital      |
+---------+------------+-------------+-----------------+-------------------+------------------+------------------+
| A       | 2005-06-30 |    0.014419 |         2000.00 |              0.00 |           28.838 |          -28.838 |
| A       | 2005-07-31 |      0.0149 |         2028.84 |             35.88 |       30.2296862 |        5.6503138 |
| A       | 2005-08-31 |      0.0149 |         2023.19 |             35.88 |   30.14552632438 | 5.73447367562001 |
| A       | 2005-09-30 |    0.014419 |         2017.46 |             35.88 | 29.0896912340712 | 6.79030876592877 |
| A       | 2005-10-31 |      0.0149 |         2010.67 |             35.88 | 29.9589783993877 | 5.92102160061234 |
| A       | 2005-11-30 |    0.014419 |         2004.75 |             35.88 | 28.9064755195408 | 6.97352448045923 |
| A       | 2005-12-31 |      0.0149 |         1997.78 |             35.88 | 29.7668694852412 | 6.11313051475884 |
| A       | 2006-01-31 |      0.0149 |         1991.67 |             35.88 | 29.6758363553301 | 6.20416364466991 |
| A       | 2006-02-28 |    0.013458 |         1985.47 |             35.88 |   26.72039922567 | 9.15960077432997 |
| A       | 2006-03-31 |      0.0149 |         1976.31 |             35.88 | 29.4470249484625 | 6.43297505153752 |
| A       | 2006-04-30 |    0.014419 |         1969.88 |             35.88 | 28.4036568227319 | 7.47634317726812 |
| A       | 2006-05-31 |      0.0149 |         1962.40 |             35.88 | 29.2398144866587 | 6.64018551334129 |
| A       | 2006-06-30 |    0.014419 |         1955.76 |             35.88 | 28.2001007650831 | 7.67989923491687 |
| A       | 2006-07-31 |      0.0149 |         1948.08 |             35.88 | 29.0263935013997 | 6.85360649860026 |
| A       | 2006-08-31 |      0.0149 |         1941.23 |             35.88 | 28.9242732631709 | 6.95572673682915 |
| A       | 2006-09-30 |    0.014419 |         1934.27 |             35.88 | 27.8903007461817 | 7.98969925381834 |
| A       | 2006-10-31 |      0.0149 |         1926.28 |             35.88 | 28.7015764811181 |  7.1784235188819 |
| A       | 2006-11-30 |    0.014419 |         1919.10 |             35.88 | 27.6715256312812 | 8.20847436871876 |
| A       | 2006-12-31 |      0.0149 |         1910.89 |             35.88 | 28.4722837319061 | 7.40771626809391 |
| A       | 2007-01-31 |      0.0149 |         1903.48 |             35.88 | 28.3618860276054 |  7.5181139723946 |
| B       | 2005-06-30 |    0.014419 |         4000.00 |              0.00 |           57.676 |          -57.676 |
| B       | 2005-07-31 |      0.0149 |         4057.68 |             71.76 |       60.4593724 |       11.3006276 |
| B       | 2005-08-31 |      0.0149 |         4046.38 |             71.76 |   60.29105264876 |   11.46894735124 |
| B       | 2005-09-30 |    0.014419 |         4034.91 |             71.76 | 58.1793824681425 | 13.5806175318575 |
| B       | 2005-10-31 |      0.0149 |         4021.33 |             71.76 | 59.9178077987753 | 11.8421922012247 |
| B       | 2005-11-30 |    0.014419 |         4009.49 |             71.76 | 57.8128047006505 | 13.9471952993495 |
| B       | 2005-12-31 |      0.0149 |         3995.54 |             71.76 | 59.5335877900397 | 12.2264122099603 |
| B       | 2006-01-31 |      0.0149 |         3983.31 |             71.76 | 59.3513724580716 | 12.4086275419284 |
| B       | 2006-02-28 |    0.013458 |         3970.90 |             71.76 | 53.4403906705407 | 18.3196093294593 |
| B       | 2006-03-31 |      0.0149 |         3952.58 |             71.76 | 58.8934478209911 | 12.8665521790089 |
| B       | 2006-04-30 |    0.014419 |         3939.71 |             71.76 | 56.8067282041309 | 14.9532717958691 |
| B       | 2006-05-31 |      0.0149 |         3924.76 |             71.76 | 58.4788752502416 | 13.2811247497585 |
| B       | 2006-06-30 |    0.014419 |         3911.48 |             71.76 | 56.3996139022332 | 15.3603860977668 |
| B       | 2006-07-31 |      0.0149 |         3896.12 |             71.76 | 58.0521822471433 | 13.7078177528567 |
| B       | 2006-08-31 |      0.0149 |         3882.41 |             71.76 | 57.8479415154824 | 13.9120584845176 |
| B       | 2006-09-30 |    0.014419 |         3868.50 |             71.76 | 55.7798718187117 | 15.9801281812883 |
| B       | 2006-10-31 |      0.0149 |         3852.52 |             71.76 | 57.4025460900988 | 14.3574539099012 |
| B       | 2006-11-30 |    0.014419 |         3838.16 |             71.76 | 55.3424657520731 | 16.4175342479269 |
| B       | 2006-12-31 |      0.0149 |         3821.74 |             71.76 | 56.9439627397059 | 14.8160372602941 |
| B       | 2007-01-31 |      0.0149 |         3806.92 |             71.76 | 56.7231670448216 | 15.0368329551784 |
+---------+------------+-------------+-----------------+-------------------+------------------+------------------+

【讨论】：

@imdave 的 CTE 在性能方面更好吗？因为我觉得我会更多地控制光标。此外，我有多个帐户，因此查询的第一部分与前 1 部分无关
游标在几乎所有情况下都会有最差的性能。如果您更新示例数据以包含多个帐户，则可以对其进行修改以处理那些没有太多问题的情况。
@AamirKhan 我已经更新了我的脚本以将计算拆分为不同的Accounts
我已经为您添加了新数据。谢谢
@AamirKhan 已更新以使用您的数据。

【解决方案2】：

您可以使用 CTE 尝试类似的操作。
在 CTE 构造中，它使用 ROW_NUMBER 将每一行与前一行链接，并按照您的描述计算各种数量。

    WITH  X AS (SELECT [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Monthly Repayment]-[Opening Balance]* [Rate Charge] AS [Capital]
                       , ROW_NUMBER() OVER (ORDER BY  [Month]) AS RN
                FROM [example_2]                                        
                )
    , X2 AS (SELECT [Month]
                   , [Rate Charge]
                   , [Opening Balance]
                   , [Monthly Repayment]
                   , [Interest]=[Opening Balance]*[Rate Charge]
                   , [Capital]
                   , RN
                FROM X WHERE RN=1
                UNION ALL
                SELECT X.[Month]
                   , X.[Rate Charge]
                   , CAST( XX1.[Opening Balance]-XX1.Capital AS money) AS [Opening Balance]
                   , X.[Monthly Repayment]
                   , (XX1.[Opening Balance]-XX1.Capital)*X.[Rate Charge] AS [Interest]
                      , X.[Monthly Repayment]-(XX1.[Opening Balance]-XX1.Capital)*X.[Rate Charge] AS [Capital]
                   , X.RN               
                FROM X 
                INNER JOIN X2 XX1 ON X.RN=XX1.RN+1
                )
   SELECT [Month], [Rate Charge], [Opening Balance], [Monthly Repayment], [Interest], [Capital]
   FROM X2;

输出：

Month      Rate Charge            Opening Balance       Monthly Repayment     Interest               Capital
---------- ---------------------- --------------------- --------------------- ---------------------- ----------------------
2005-06-30 0.014419               2000.00               0.00                  28.838                 -28.838
2005-07-31 0.0149                 2028.838              35.88                 30.2296862             5.6503138
2005-08-31 0.0149                 2023.1877             35.88                 30.14549652438         5.73450347562
2005-09-30 0.014419               2017.4532             35.88                 29.089657640685        6.79034235931497
2005-10-31 0.0149                 2010.6629             35.88                 29.9588765788462       5.9211234211538
2005-11-30 0.014419               2004.7418             35.88                 28.9063716764904       6.97362832350962
2005-12-31 0.0149                 1997.7682             35.88                 29.7667457579797       6.1132542420203
2006-01-31 0.0149                 1991.6549             35.88                 29.6756586917939       6.2043413082061
2006-02-28 0.013458               1985.4506             35.88                 26.7201936188742       9.15980638112584
2006-03-31 0.0149                 1976.2908             35.88                 29.4467328249212       6.43326717507878
2006-04-30 0.014419               1969.8575             35.88                 28.4033757658025       7.47662423419746
2006-05-31 0.0149                 1962.3809             35.88                 29.2394750489105       6.64052495108955
2006-06-30 0.014419               1955.7404             35.88                 28.1998204678302       7.68017953216976
2006-07-31 0.0149                 1948.0602             35.88                 29.0260972849707       6.85390271502934
2006-08-31 0.0149                 1941.2063             35.88                 28.9239738295461       6.95602617045394
2006-09-30 0.014419               1934.2503             35.88                 27.8899546983482       7.99004530165178
2006-10-31 0.0149                 1926.2603             35.88                 28.7012777950054       7.17872220499462
2006-11-30 0.014419               1919.0816             35.88                 27.6712372702262       8.20876272977382
2006-12-31 0.0149                 1910.8728             35.88                 28.4720052753264       7.40799472467363
2007-01-31 0.0149                 1903.4648             35.88                 28.3616255986024       7.51837440139764

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