Get running balance of a work center using partition - sql-server

Question

I am writing a script that will run on SQL Server 2014.
I have a table of transactions recording transfers from one work center to another. The simplified table is below:
DECLARE #transactionTable TABLE (wono varchar(10),transferDate date
,fromWC varchar(10),toWC varchar(10),qty float)
INSERT INTO #transactionTable
SELECT '0000000123','5/10/2018','STAG','PP-B',10
UNION
SELECT '0000000123','5/11/2018','PP-B','PP-T',5
UNION
SELECT '0000000123','5/11/2018','PP-T','TEST',3
UNION
SELECT '0000000123','5/12/2018','PP-B','PP-T',5
UNION
SELECT '0000000123','5/12/2018','PP-T','TEST',5
UNION
SELECT '0000000123','5/13/2018','PP-T','TEST',2
UNION
SELECT '0000000123','5/13/2018','TEST','FGI',8
UNION
SELECT '0000000123','5/14/2018','TEST','FGI',2
SELECT *,
fromTotal = -SUM(qty) OVER(PARTITION BY fromWC ORDER BY wono, transferdate, fromWC),
toTotal = SUM(qty) OVER(PARTITION BY toWC ORDER BY wono, transferdate, toWC)
FROM #transactionTable
ORDER BY wono, transferDate, fromWC
I want to get a running balance of the fromWC and toWC after each transaction.
Given the records above, the end result should be this:
I believe it is possible to use SUM(qty) OVER(PARTITION BY..., but I am not sure how to write the statement. When I try to get the increase and decrease, each line always results in 0.
How do I write the SUM statement to achieve the desired results?
UPDATE
This image shows each transaction, the resulting WC qty, and highlights the corresponding from and to work centers for each transaction.
For example, looking at the second record on 5/11, 3 were transferred from PP-T to TEST. After the transaction, there were 5 in PP-B, 2 in PP-T, and 3 in TEST.

Answer 1

I can get close, except starting balances:
SELECT wono, transferDate, fromWC, toWC, qty,
SUM( CASE WHEN WC = fromWC THEN RunningTotal ELSE 0 END ) AS FromQTY,
SUM( CASE WHEN WC = toWC THEN RunningTotal ELSE 0 END ) AS ToQTY
FROM( -- b
SELECT *, SUM(Newqty) OVER(PARTITION BY WC ORDER BY wono,transferdate, fromWC, toWC) AS RunningTotal
FROM(-- a
SELECT wono, transferDate, fromWC, toWC, fromWC AS WC, qty, -qty AS Newqty, 'From' AS RecType
FROM #transactionTable
UNION ALL
SELECT wono, transferDate, fromWC, toWC, toWC AS WC, qty, qty AS Newqty, 'To' AS RecType
FROM #transactionTable
) AS a
) AS b
GROUP BY wono, transferDate, fromWC, toWC, qty
My logic assumes that all balances start at 0, therefore "STAG" balance will be -10.
How the query works:
"Unpivot" the input record set into "From" and "To" records with quantities negated for "From" records.
Calculate running totals for each "WC".
Combine "Unpivoted" records back into original shape
Solution 2
WITH CTE
AS(
SELECT *,
ROW_NUMBER() OVER( ORDER BY wono, transferDate, fromWC, toWC ) AS Sequence
FROM #transactionTable
),
CTE2
AS(
SELECT *,
fromTotal = -SUM(qty) OVER(PARTITION BY fromWC ORDER BY Sequence),
toTotal = SUM(qty) OVER(PARTITION BY toWC ORDER BY Sequence)
FROM CTE
)
SELECT a.Sequence, b.Sequence, c.Sequence, a.wono, a.transferDate, a.fromWC, a.toWC, a.qty, a.fromTotal + ISNULL( b.toTotal, 0 ) AS FromTotal, a.toTotal + ISNULL( c.fromTotal, 0 ) AS ToTotal
FROM CTE2 AS a
OUTER APPLY( SELECT TOP 1 * FROM CTE2 WHERE wono = a.wono AND Sequence < a.Sequence AND toWC = a.fromWC ORDER BY Sequence DESC ) AS b
OUTER APPLY( SELECT TOP 1 * FROM CTE2 WHERE wono = a.wono AND Sequence < a.Sequence AND fromWC = a.toWC ORDER BY Sequence DESC ) AS c
ORDER BY a.Sequence
Note: This solution would benefit greatly from an "ID" column, that mirrors transaction order OR at least you will need an index on wono, transferDate, fromWC, toWC