如何從兩個數據表中減去相似列和值的行

Question

如何從兩個SQL數據表中減去值？ 在圖片中，我有兩個數據表，我要首先匹配table1“ partnum”列，如果它與表2“ partnum”匹配，則從table2“ FinalStockout”中減去table1“ FinalstockIN”的值，然后將其顯示在另一列中。

我從其他人的建議中嘗試了什么，但這也沒有顯示完整的數據。

with spare_parts as (

SELECT s.partnum,partdesc,partmodel,stockin,dateofstockin, (SELECT 
SUM(stockin)
FROM Tbl_SpareParts
GROUP BY partnum
HAVING partnum = s.partnum) AS FinalTotalStockIN FROM Tbl_SpareParts s
),
cases as (
SELECT 
b.partnum,partdesc,partmodel,outstock,outstockdate,
outstockcaseid_billnum,remarks, (SELECT SUM(outstock)
FROM Tbl_OutCaseID
GROUP BY partnum
HAVING partnum = b.partnum) AS FinalTotalStockOut FROM Tbl_OutCaseID b
)
select
s.partnum, s.partdesc, s.partmodel, s.stockin, 
s.dateofstockin, s.FinalTotalStockIN,
c.partnum AS Stockoutpartnum, 
c.partdesc AS Stockoutpartdesc, 
c.partmodel AS stockoutpartmodel, c.outstock, 
c.outstockdate, c.outstockcaseid_billnum, 
c.remarks, c.FinalTotalStockOut
from
spare_parts s
join cases c on s.partnum = c.partnum

Answer 1

SELECT STOCKOUTPARTNUM,STOCKOUTPARTNUM,NULL FROM TABLE 2 MINUS SELECT PARTNUM,NULL,PARTNUM FROM TABLE 1

數據類型必須與STOCKOUTPARTNUM，PARTNUM相同