问题
Good morning.
I am trying to solve an issue that is very similar to the post below, but with 1 extra parameter that is tripping me up.
SQL Server Query, running total in view, reset when column A changes
In the answer to this question, the code below was provided.
Original Code
DECLARE @T TABLE (Category VARCHAR(5), Value INT)
INSERT INTO @T VALUES
('Cat A', 10),
('Cat A', 20),
('Cat A', 30),
('Cat B', 15),
('Cat B', 15),
('Cat C', 10),
('Cat C', 10)
;WITH T AS
( SELECT Category, Value, ROW_NUMBER() OVER(PARTITION BY Category ORDER BY Value) [RowNumber]
FROM @T
)
SELECT T1.Category,
T1.Value,
RunningTotal
FROM T T1
OUTER APPLY
( SELECT SUM(Value) [RunningTotal]
FROM T T2
WHERE T2.Category = T1.Category
AND T2.RowNumber <= T1.RowNumber
) RunningTotal
This solution works correctly if the categories should go in order; however if for example the order goes A, A, A, B, B, C, C, A, A, B then all the As will be grouped at the top followed by B, etc and the order will not be maintained. This can be seen below:
Extended Sample
DECLARE @T TABLE (Category VARCHAR(5), Value INT)
INSERT INTO @T VALUES
('Cat A', 10),
('Cat A', 20),
('Cat A', 30),
('Cat B', 15),
('Cat B', 15),
('Cat C', 10),
('Cat C', 10),
('Cat A', 100),
('Cat A', 05),
('Cat B', 15)
;WITH T AS
( SELECT Category, Value, ROW_NUMBER() OVER(PARTITION BY Category ORDER BY Value) [RowNumber]
FROM @T
)
SELECT T1.Category,
T1.Value,
RunningTotal
FROM T T1
OUTER APPLY
( SELECT SUM(Value) [RunningTotal]
FROM T T2
WHERE T2.Category = T1.Category
AND T2.RowNumber <= T1.RowNumber
) RunningTotal
Sample Code Output
╔══════════╦════════╦═══════════════╗
║ Category ║ Amount ║ Running Total ║
╠══════════╬════════╬═══════════════╣
║ Cat A ║ 5 ║ 5 ║
║ Cat A ║ 10 ║ 15 ║
║ Cat A ║ 20 ║ 35 ║
║ Cat A ║ 30 ║ 65 ║
║ Cat A ║ 100 ║ 165 ║
║ Cat B ║ 15 ║ 15 ║
║ Cat B ║ 15 ║ 30 ║
║ Cat B ║ 15 ║ 45 ║
║ Cat C ║ 10 ║ 10 ║
║ Cat C ║ 10 ║ 20 ║
╚══════════╩════════╩═══════════════╝
Required Output
I have added one more column to this to illustrate my example. As you can see below, the table is sorted by Date so the Category stays in that order; however the Running total resets every time the Category changes.
╔══════════╦════════╦═══════════════╦════════════╗
║ Category ║ Amount ║ Running Total ║ Date ║
╠══════════╬════════╬═══════════════╬════════════╣
║ Cat A ║ 10 ║ 10 ║ 23/10/2015 ║
║ Cat A ║ 20 ║ 30 ║ 17/10/2015 ║
║ Cat A ║ 30 ║ 60 ║ 15/10/2015 ║
║ Cat B ║ 15 ║ 15 ║ 02/10/2015 ║
║ Cat B ║ 15 ║ 30 ║ 24/09/2015 ║
║ Cat C ║ 10 ║ 10 ║ 17/09/2015 ║
║ Cat C ║ 10 ║ 20 ║ 14/09/2015 ║
║ Cat A ║ 100 ║ 100 ║ 12/09/2015 ║
║ Cat A ║ 5 ║ 105 ║ 08/09/2015 ║
║ Cat B ║ 15 ║ 15 ║ 03/09/2015 ║
╚══════════╩════════╩═══════════════╩════════════╝
Example When Dates Are The Same
Note that the first 2 entries have the same date.
╔══════════╦═══════╦════════════╦══════════════╗
║ Category ║ Value ║ Date ║ RunningTotal ║
╠══════════╬═══════╬════════════╬══════════════╣
║ Cat A ║ 10 ║ 30/05/2015 ║ 30 ║
║ Cat A ║ 20 ║ 30/05/2015 ║ 30 ║
║ Cat A ║ 30 ║ 28/05/2015 ║ 60 ║
║ Cat B ║ 15 ║ 27/05/2015 ║ 15 ║
║ Cat B ║ 15 ║ 26/05/2015 ║ 30 ║
║ Cat C ║ 10 ║ 25/05/2015 ║ 10 ║
║ Cat C ║ 10 ║ 24/05/2015 ║ 20 ║
║ Cat A ║ 100 ║ 23/05/2015 ║ 100 ║
║ Cat A ║ 5 ║ 22/05/2015 ║ 105 ║
║ Cat B ║ 15 ║ 21/05/2015 ║ 15 ║
╚══════════╩═══════╩════════════╩══════════════╝
The number of categories can change and could be up to 100 different values.
This query will be used in an SSRS report so if anyone can help me with an SSRS example, that would be great, if not then just the SQL would also be amazing.
Many thanks,
Ninja.
回答1:
Here is an example. First you are getting islands and then calculating running total:
DECLARE @T TABLE (Category VARCHAR(5), Value INT, Date DATE)
INSERT INTO @T VALUES
('Cat A', 10, '20150530'),
('Cat A', 20, '20150529'),
('Cat A', 30, '20150528'),
('Cat B', 15, '20150527'),
('Cat B', 15, '20150526'),
('Cat C', 10, '20150525'),
('Cat C', 10, '20150524'),
('Cat A', 100, '20150523'),
('Cat A', 05, '20150522'),
('Cat B', 15, '20150521')
;WITH cte AS(SELECT *, ROW_NUMBER() OVER(Order By date DESC)
- ROW_NUMBER() OVER(Partition By Category Order By date DESC) rn FROM @t)
SELECT * FROM cte c1
CROSS APPLY(SELECT SUM(c2.Value) AS RunningTotal FROM cte c2
WHERE c2.rn = c1.rn AND c2.Category = c1.Category AND c2.Date >= c1.Date) ca
ORDER BY c1.Date desc
Output:
Category Value Date rn RunningTotal
Cat A 10 2015-05-30 0 10
Cat A 20 2015-05-29 0 30
Cat A 30 2015-05-28 0 60
Cat B 15 2015-05-27 3 15
Cat B 15 2015-05-26 3 30
Cat C 10 2015-05-25 5 10
Cat C 10 2015-05-24 5 20
Cat A 100 2015-05-23 4 100
Cat A 5 2015-05-22 4 105
Cat B 15 2015-05-21 7 15
EDIT:
Simply add another cte above to give unambiguous ordering:
;WITH cte1 AS(SELECT *, ROW_NUMBER() OVER(Order By date DESC) rn1 FROM @T),
cte2 AS(SELECT *, ROW_NUMBER() OVER(Order By rn1)
- ROW_NUMBER() OVER(Partition By Category Order By rn1) rn2 FROM cte1)
SELECT * FROM cte2 c1
CROSS APPLY(SELECT SUM(c2.Value) AS RunningTotal FROM cte2 c2
WHERE c2.rn2 = c1.rn2 AND c2.Category = c1.Category AND c2.rn1 <= c1.rn1) ca
ORDER BY c1.Date desc
来源：https://stackoverflow.com/questions/33298291/running-total-that-changes-each-time-a-column-value-changes