SQL 在 Oracle 查询中减去两个数字列值
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时间：2020-09-01 04:45:09 来源:igfitidea点击:
Subtract two numeric column values in Oracle query
提问by Charles Bretana
I need to subtract two column values and display the output column in select query.
我需要减去两列值并在选择查询中显示输出列。
SELECT c.name,
(SELECT SUM(p.qty*s.price)
FROM stock s, purchase p
WHERE s.company = p.company
GROUP BY p.company)
MINUS
(SELECT SUM(p.price*p.qty)
FROM stock s, purchase p
WHERE s.company = p.company
GROUP BY p.company) AS "Profit/Lost"
FROM purchase p, client c, stock s
WHERE s.company = p.company
AND c.clno = p.clno
GROUP BY p.company;
But it will display an error. How to solve?
但它会显示错误。怎么解决？
回答by Charles Bretana
First subquery needs an Alias.
第一个子查询需要一个别名。
but why use subquery at all? Is this what you want?
但是为什么要使用子查询呢？这是你想要的吗？
SELECT c.name, p.company,
SUM(p.qty*s.price) - SUM(p.price*p.qty) roe
FROM client c
join purchase p on p.clno = c.clno
join stock s on s.company = p.company
GROUP BY c.name, p.company;
