How to fix this logic? - sql-server

Question

i have a query with 3 variable tables: #result, #order and #stock.
the logic is the stock qty must be allocated by lotsize (here i set=1) to all order based on priority (FIFO). the stock qty must be allocated till zero and the allocateqty must <= orderqty. the problem is one of orders, its allocateqty is over orderqty (priority=7) while other are correct.
DECLARE #RESULT TABLE (priority int,partcode nvarchar(50),orderqty int, runningstock int, allocateqty int)
DECLARE #ORDER TABLE(priority int,partcode nvarchar(50),orderqty int)
DECLARE #STOCK TABLE(partcode nvarchar(50),stockqty int)
INSERT INTO #ORDER (priority,partcode,orderqty)
VALUES (1,'A',10),
(2,'A',50),
(3,'A',10),
(4,'A',40),
(5,'A',3),
(6,'A',5),
(7,'A',11),
(8,'A',10),
(9,'A',10),
(10,'A',10);
INSERT INTO #STOCK(partcode,stockqty)
VALUES('A',120)
IF (SELECT SUM(orderqty)FROM #ORDER)<(SELECT stockqty FROM #STOCK)
BEGIN
INSERT INTO #RESULT(priority,partcode,orderqty,allocateqty)
SELECT priority, partcode,orderqty,orderqty
FROM #ORDER
END
ELSE
BEGIN
DECLARE #allocatedqty int = 0
DECLARE #Lotsize int=1
DECLARE #allocateqty int = #Lotsize
DECLARE #runningstock int = (SELECT stockqty FROM #stock)
WHILE #runningstock>=0
BEGIN
DECLARE #priority int
SELECT TOP 1 #priority = priority FROM #order ORDER BY priority ASC
WHILE #priority <= (SELECT MAX(priority) FROM #order)
BEGIN
DECLARE #orderqty int
SELECT #orderqty = orderqty - #allocatedqty FROM #order WHERE priority = #priority
SELECT #allocateqty = CASE WHEN #runningstock > 0 AND #orderqty > 0 THEN #Lotsize ELSE 0 END
INSERT INTO #RESULT(priority,partcode,orderqty,runningstock,allocateqty)
SELECT #priority,
partcode,
CASE WHEN #orderqty >= 0 THEN #orderqty ELSE 0 END AS orderqty,
#runningstock,
#allocateqty
FROM #order
WHERE priority = #priority
SET #priority += 1
SET #runningstock = #runningstock - #allocateqty
END
SET #allocatedqty += #allocateqty
IF (#runningstock <= 0) BREAK
END
END
select * from #RESULT where priority=7;
SELECT priority,
sum(allocateqty) as allocated
from #RESULT
group by priority
the result:

Answer 1

my reputation not reach 50 so cant add comment.
you said your other order is correct then priority = 7 is also correct. you can compare priority 2 and 4 with 7. its the same thing. i think all of your loop for orderqty only reach 10 times where priority 7 got 11 so it will left 1.
Either everything is correct or everything is wrong =x
EDIT:
Hi, I found the answer.
Change
SET #allocatedqty += #allocateqty
to
SET #allocatedqty += 1
because when using SET #allocatedqty += #allocateqty, the last order #allocateqty is 0 then it will always make #allocatedqty = 0 then it will not increase.
Hope this really help you.
EDIT based on #Jesuraja given answer it should be:
SET #allocatedqty += #Lotsize

Answer 2

As I'm not quite sure what you try to achieve with records which will set your stock to 0 or beyond I just can provide this. But it is much better than to run all your orders in a loop. Maybe you'll want to replace your loop.
DECLARE #RESULT TABLE (priority int,partcode nvarchar(50),orderqty int, runningstock int, allocateqty int)
DECLARE #ORDER TABLE(priority int,partcode nvarchar(50),orderqty int)
DECLARE #STOCK TABLE(partcode nvarchar(50),stockqty int)
INSERT INTO #ORDER (priority,partcode,orderqty)
--VALUES (1,'A',10),(2,'A',50),(3,'A',10),(4,'A',40),(5,'A',3),(6,'A',5),(7,'A',11),(8,'A',10),(9,'A',10),(10,'A',10); --your orders
VALUES (1,'A',1),(2,'A',2),(3,'A',3),(4,'A',4),(5,'A',5),(6,'A',6),(7,'A',7),(8,'A',8),(9,'A',9),(10,'A',10);
INSERT INTO #STOCK(partcode,stockqty)
--VALUES('A',50) -- your stock
VALUES('A',50)
IF (SELECT SUM(orderqty) FROM #ORDER)<(SELECT stockqty FROM #STOCK)
BEGIN
INSERT INTO #RESULT(priority,partcode,orderqty,allocateqty)
SELECT priority, partcode,orderqty,orderqty
FROM #ORDER
END
ELSE
BEGIN
;WITH dat AS(
SELECT s.partcode, s.stockqty, o.priority, o.orderqty,
ROW_NUMBER() OVER(PARTITION BY s.partcode ORDER BY o.priority DESC) as runningOrder
FROM #Stock as s
INNER JOIN #ORDER as o
ON s.partcode = o.partcode
)
INSERT INTO #RESULT(priority,partcode,orderqty,runningstock,allocateqty)
SELECT d1.priority, d1.partcode, d1.orderqty,
d1.stockqty - SUM(d2.orderqty) OVER(PARTITION BY d1.runningOrder) as runningstock,
CASE WHEN d1.stockqty - SUM(d2.orderqty) OVER(PARTITION BY d1.runningOrder) > 0 AND d1.orderqty > 0 THEN 1 ELSE 0 END
FROM dat as d1
INNER JOIN dat as d2
ON d1.partcode = d2.partcode
AND d1.runningOrder >= d2.runningOrder
END
select * from #RESULT where priority=7;
SELECT priority,
sum(allocateqty) as allocated
from #RESULT
group by priority