更新基於訂單的庫存表數量

Question

我無法創建基於入站訂單表更新庫存表的SQL語句。

入境

OrderID ProductID Description ShipQty 
001  2   Apple  3 
002  4   Orange  4 
003  1   Grape  1 
004  2   Apple  6 
005  5   Strawberry 3 
006  3   Pear   1 
007  1   Grape  2 

庫存

ProductID Description Qty 
1   Grape  10 
2   Apple  10 
3   Pear   10 
4   Orange  10 
5   Strawberry 10 

哪些廣告看起來應該更新後

ProductID Description Qty 
1   Grape  13 
2   Apple  19 
3   Pear   11 
4   Orange  14 
5   Strawberry 13 

Answer 1

你可以試試這個：

UPDATE INVENTORY 
SET Qty = Qty + (SELECT SUM(ShipQty) FROM INBOUND WHERE ProductID = INVENTORY.ProductID) 

Answer 2

嘗試如下：

update INVENTORY 
set qty = qty + TotalQty 
from (
select INBOUND.ProductID, sum(shipqty) as TotalQty 
from INBOUND 
group by INBOUND.ProductID 
) as a 
where a.ProductID = INVENTORY.ProductID