Get the ranges from the table on the basis of value - sql

Question

I have some specific transaction count value and I have to check if that count lies within what range. The ranges are specified in the below table. For example, if the count value is >= 1 AND less than 250001 from the range_start column then the count lies with range_id 1.
The tricky part is that if the transaction count on the first day of the month is greater than 1 and less than 31 and lies in range_id 3 then I have to divide the count into 3 bands for example if I have 30 transactions on the first day of the month then I will calculate the fees for the 10 transactions on the basis of range_id 1, and for the other 10 the fees would be calculated on the basis of range_id 2 and the remaining 10 transactions would be calculated on the range_id 3. Now on the second day of the month fees calculation would start from band 3 and it will keep moving to the next bands as the transaction volume would increase.
More Exaplanation:
Fees calculation is like this:
Total Transactions on first day of the month are:30
Auth Fees for First 10 transaction would be 10 * 0.1698 (range_id 1) = 1.698
Auth Fees the other 10 transactions would be 10 * 0.1536 (range_id 2)= 1.536
Auth Fees the other 10 transactions would be 10 * 0.1403 (range_id 3)= 1.403
Total Transactions on the second day of the month are : 20
Auth Fees for first 10 transactions would be 10 * 1.403 (range_id 4) = 14.03
Auth Fees for second 10 transactions would be 10 * 0.1036 (range_id 5) = 1.036
Total Transactions on the third day of the month are : 5
Auth Fees for 5 transactions would be 5 * 1.036 (range_id 6) = 5.18
I am saving the daily transaction count in a table, for example for the first day it would be 30,
for the second day it would be 50 and for the third day it would be 55 and on the first day of the month it would be reset to 0.
The fees calculation is daily and the transaction table will only have data for one day and at the end of the calculation, the transaction table is dropped, So I am keeping the total count for the previous business day in the table(gstl_daily_volume) as well in order to calculate the range_id next day.
I have achieved the band calculation with the below queries but the problem with this is that it can only calculate the fees accurately for one day and for the second day it starts again from the range_id 1 as it is not considering the volume of the previous day from gstl_daily_volume table. Please help me understand how can I continue on the second day from where I left off on first day of the month while considering the volume of the previous day.
declare #rangeTable TABLE
(
rangeId INT,
rangeStart INT,
rangeEnd INT NULL,
authFees decimal(8,4),
settlementFees decimal(8,4),
declinedFees decimal(8,4)
)
insert into #rangeTable
values
(1, 1, 11, 0.1698, 0.1359, 0.3284),
(2, 11, 21, 0.1536, 0.1536, 0.3280),
(3, 21, 31, 0.1403, 0.1330, 0.3278),
(4, 31, 41, 0.1203, 0.1320, 0.3276),
(5, 41, 51, 0.1036, 0.1310, 0.3274),
(6, 51, NULL, 0.0873, 0.1300, 0.3272)
declare #transactionsTable TABLE
(
transactionId INT IDENTITY(1,1),
transactionDate DateTime,
transactionAmount decimal(8,2)
)
insert into #transactionsTable
values
(N'2020-12-01', 500),
(N'2020-12-01', 501)
--- calculate per date total transaction fees
select
Datee = CAST(C.transactionDate AS DATE),
TotalSettlememtFee = SUM(C.settlementFees)
From
(
select
*
-- each transaction counts as 1
--,AuthFee = 1 * B.authFees
--,SettlememtFee = 1 * settlementFees
from
(
-- set a row number or transaction number per transaction which resets every month
select
rowNumber = ROW_NUMBER() OVER(PARTITION BY DATEPART(MONTH, transactionDate), DATEPART(YEAR, transactionDate) ORDER BY transactionDate),
*
from #transactionsTable tt
) A
-- cross apply to calculate which range for each transaction
CROSS APPLY
(
select
*
From #rangeTable rtt
where A.rowNumber >= rtt.rangeStart
AND A.rowNumber < rtt.rangeEnd
) B
) C
-- group by date to get the per date fees
group by CAST(C.transactionDate AS DATE)
Daily Volume table where The total count would be saved for each day:
GO
/****** Object: Table [dbo].[gstl_daily_volume] Script Date: 1/4/2021 5:50:08 PM ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[gstl_daily_volume](
[business_date] [datetime] NULL,
[record_type] [varchar](50) NULL,
[total_count] [varchar](50) NULL,
[band_id] [bigint] NULL
) ON [PRIMARY]
GO
Please help, thanks in advance.

Answer 1

As the transactions table is a staging table, i.e. it only has data for current day - and gets empty end of the day.
I think if you add the previous days transaction count in your calculated row number this will work as expected.
DECLARE #previousDayTransactionCount INT;
-- TODO: set this to MAX from gstl_daily_volume for current month
--- calculate per date total transaction fees
select
Datee = CAST(C.transactionDate AS DATE),
TotalSettlememtFee = SUM(C.settlementFees)
From
(
select
*
-- each transaction counts as 1
--,AuthFee = 1 * B.authFees
--,SettlememtFee = 1 * settlementFees
from
(
-- set a row number or transaction number per transaction which resets every month
-- Then Add it here to current calculated rowNumber
select
rowNumber = #previousDayTransactionCount + (ROW_NUMBER() OVER(PARTITION BY DATEPART(MONTH, transactionDate), DATEPART(YEAR, transactionDate) ORDER BY transactionDate)),
*
from #transactionsTable tt
) A
-- cross apply to calculate which range for each transaction
CROSS APPLY
(
select
*
From #rangeTable rtt
where A.rowNumber >= rtt.rangeStart
AND A.rowNumber < rtt.rangeEnd
) B
) C
-- group by date to get the per date fees
group by CAST(C.transactionDate AS DATE)