SQL Server: get weekly deposit changes using recursive CTE - sql-server

Question

I have a table with account deposits.
+-----------+------------+-----------+
| DepositId | Date | Amount |
+-----------+------------+-----------+
| 1 | 2014-06-12 | 2342,00 |
| 2 | 2014-08-05 | 23423,00 |
| 3 | 2014-09-07 | 7745,00 |
|....................................|
| 12 | 2014-12-05 | 35435,00 |
| 13 | 2014-12-11 | 353453,00 |
| 14 | 2014-12-29 | 53453,00 |
+-----------+------------+-----------+
I want to see weekly balance change like this:
+------------+----------+
| Date | Amount |
+------------+----------+
| 2014-10-07 | 74754,00 |
| 2014-10-14 | 74754,00 |
| 2014-10-21 | 6353,00 |
| 2014-10-28 | 6353,00 |
| ........ | ...... |
| 2014-12-30 | 53453,00 |
+------------+----------+
To see this changes for past 3 month (~ 13 weeks) I can use this queries:
select CONVERT(date, DATEADD(WEEK, -13, GETDATE())) as Date, ad.Amount
from AccountDeposits as ad
inner join
(select Max(Date) as Date
from AccountDeposits
where (Date < DATEADD(WEEK, -13, GETDATE())))
as ad2 on (ad.Date = ad2.Date)
union all
select CONVERT(date, DATEADD(WEEK, -12, GETDATE())) as Date, ad.Amount
from AccountDeposits as ad
inner join
(select Max(Date) as Date
from AccountDeposits
where (Date < DATEADD(WEEK, -12, GETDATE())))
as ad2 on (ad.Date = ad2.Date)
......................................................
select CONVERT(date, DATEADD(WEEK, -1, GETDATE())) as Date, ad.Amount
from AccountDeposits as ad
inner join
(select Max(Date) as Date
from AccountDeposits
where (Date < DATEADD(WEEK, -1, GETDATE())))
as ad2 on (ad.Date = ad2.Date)
I have to do this with recursive Common Table Expressions but in recursive part of CTE I can't use MAX() function. How I should write this query series to on query with CTE?

Answer 1

I may have misinterpreted the question (apologies if I have) but if the question is "for each week when there were deposits, give the sum of the total deposits for that week and the last day of that week" then the T-SQL below would give the correct results.
with myCte1 as
(
select *, datepart(week,d.[Date]) as wk, datepart(year,d.[Date]) as yr,
dateadd(dd, 7-(datepart(dw,d.[Date])), d.[Date]) as weekEndDate
from dbo.AccountDeposits as d
),
myCte2 as
(
select *, sum(m.Amount) over (partition by m.yr, m.wk) as totalWeeklyAmt
from myCte1 as m
)
select distinct m.weekEndDate, m.totalWeeklyAmt
from myCte2 as m

Answer 2

This uses two CTE's, one summarises our source data and the other uses a recursive CTE to generate all the weeks, this allows us to also show weeks where there were no deposits. It also uses two co-related subqueries to get the sumarised data from the first CTE.
I think this satisfies the requirements of your assignment.'
--NOTE: this gets data based on week end date, so all deposits for week of #WeeksHistory ago not just the deposits after the date (today minus #WeeksHistory weeks).
--NOTE: this gets all historical data so that we can start with opening balance of $0 otherwise Closing balance wont take previous deposits into account.
--NOTE: this gets the week starting #WeeksHistory ago and also this week so you will end up with #WeeksHistory +1 records - you might want to adjust this as necessary
-- set up our source data
declare #AccountDeposits table (DepID int, AcctHolderID int, TxnDate date, Amount numeric(10,2))
insert into #AccountDeposits
values
(1, 3,'12-25-2014', 2423.00),
(2, 1,'12-13-2014',4231.00),
(3, 2,'11-01-2014',666.00),
(4, 1,'11-01-2014',4241.34),
(5, 4,'10-23-2014',4221.00),
(6, 2,'10-22-2014',9992.00),
(7, 2,'10-04-2014',3524.00),
(8, 2,'10-14-2014',3524.00),
(9, 2,'10-15-2014',3524.00),
(10, 2,'10-16-2014',3524.00),
(11, 3,'10-14-2014',3524.00),
(12, 3,'10-15-2014',3524.00),
(13, 3,'10-16-2014',3524.00),
(14, 1,'10-01-2014',3524.00),
(15, 2,'10-01-2014',3524.00),
(16, 3,'10-01-2014',3524.00),
(17, 4,'01-01-2015',3524.00)
declare #AcctHolderID as int = 2
declare #WeeksHistory int = -13
select dateadd(week,#WeeksHistory,getdate()) ThirteenWeeksAgo
;with
src (AcctHolderID, WeekEndsOn, Amount)
as (select
AcctHolderID,
DATEADD(DAY, 7-DATEPART(WEEKDAY, TxnDate), TxnDate),
SUM(Amount)
from #AccountDeposits
where AcctHolderID = #AcctHolderID -- we filter up here so that we arent processing data we dont care about.
group by
AcctHolderID,
DATEADD(DAY, 7-DATEPART(WEEKDAY, TxnDate), TxnDate)
),
r_cte (AcctHolderID, WeekEndsOn, TotalDep, ClosingBal)
as (select
AcctHolderID,
dateadd(ww,-1,Min(WeekEndsOn)),
convert(numeric(10,2),0.00),
convert(numeric(10,2),0.00)
from
src
group by
AcctHolderID
union all
select
r_cte.AcctHolderID,
dateadd(WW,1,r_cte.WeekEndsOn),
convert(numeric(10,2),ISNULL((select Amount from src where AcctHolderID = r_cte.AcctHolderID and WeekEndsOn = dateadd(WW,1,r_cte.WeekEndsOn)),0)),
convert(numeric(10,2),ISNULL((select Amount from src where AcctHolderID = r_cte.AcctHolderID and WeekEndsOn = dateadd(WW,1,r_cte.WeekEndsOn)),0) + r_cte.ClosingBal)
from
r_cte
where
AcctHolderID = r_cte.AcctHolderID
and r_cte.WeekEndsOn < DATEADD(DAY, 7-DATEPART(WEEKDAY, Getdate()), DATEADD(WW,-1,Getdate()))
)
select AcctHolderID, DATEDIFF(ww, WeekEndsOn, getdate()) as WeeksAgo, WeekEndsOn, TotalDep, ClosingBal
from r_cte
where r_cte.WeekEndsOn > dateadd(week,#WeeksHistory,getdate())
order by
AcctHolderID,
WeekEndsOn

Answer 3

I have solved it without CTE...
First create table with startdate and enddate for 13 weeks starting from getdate ().
Create table weeklydates
(Startdate date,
Enddate date
)
Declare #startdate date
Declare #enddate date
Set #startdate = cast (dateadd (week,-13,getdate ()) as date)
Set #enddate = dateadd (day,7,#startdate)
While #enddate < = getdate ()
Begin
Insert into weeklydates
Select #startdate, #enddate
Set #startdate = dateadd (day,1,#enddate)
Set #enddate = dateadd (day,7,#startdate)
End
Now use this table to display amount which will be sum of amount whose dates fall between start date and end date
Select a.startdate,a.enddate, (select sum (amount) from yourtablehavingamount as b
Where b.deposit >=a.startdate and b.deposit <=a.enddate)
From weeklydates as a

Answer 4

USE:
SELECT TOP 1 [Date]
FROM AccountDeposits
--Add WHERE Clause
ORDER BY [Date] DESC
:) David