是否可以在一个选择查询中求和?
类似这样的事情:
SELECT id, SUM(current_price - bought_price)*amount AS profit FROM purchase WHERE purchase_id = 1 GROUP BY id
我想要所有返回的利润
的总和
最佳答案
这就是你要问的:
SELECT tmp.id, SUM(tmp.profit)
FROM (
SELECT id, SUM(current_price - bought_price)*amount AS profit
FROM purchase
WHERE purchase_id = 1
GROUP BY id
) AS tmp
但是结果是一样的
SELECT SUM(current_price - bought_price)*amount AS profit
FROM purchase
WHERE purchase_id = 1
关于Mysql SUM 的 SUM,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/24779063/