Question

我有两张桌子：incomes＆amp; outgo都包含有关交易的信息。我想运行一份报告，根据表格中的总数显示整体资金流量，我目前通过使用以下查询手动执行此操作：

1) SELECT amount, SUM(amount) AS intotal FROM incomes
2) SELECT amount, SUM(amount) AS outtotal FROM outgo

例如，假设intotal为500而outtotal为300

我想要一个查询来获取摘要，并从outtotal金额减去intotal金额，在这种情况下结果为200。任何人都可以指出我正确的方向或帮助我的语法？

Answer 1

这个怎么样：

SELECT
   (SELECT SUM(amount) FROM incomes)
   -
   (SELECT SUM(amount) FROM outgo)

Answer 2

尝试

SELECT
    (SELECT amount, SUM(amount) AS intotal FROM incomes) AS a,
    (SELECT amount, SUM(id) AS outtotal FROM outgo) AS b

与a.intotal和b.outtotal

一起使用

或直接使用

SELECT 
    ((SELECT SUM(amount)FROM incomes) - (SELECT SUM(amount)FROM outgo)) AS total