获取内部联接中两行的总和 table
Getting sum of two rows in an inner joined table
我有这两张表；
- 行程
id
date
revenue
1
01/01/2020
5000
2
01/01/2020
3000
3
02/01/2020
4000
4
02/01/2020
2000
- 开支
id
tripid
amount
1
1
500
2
1
300
3
2
400
4
2
200
5
2
700
我想获得一天内收取的收入总和和一天内的支出总和。我有以下 sql 结果，但总和完全错误。
SELECT i.id, sum(i.revenue) as total, i.date trip , sum(c.amount) as exp, c.tripid expenses FROM trip i INNER JOIN expenses c ON i.id = c.tripid GROUP BY i.date ORDER BY trip DESC
您可以按行程预聚合费用，然后在外部查询中再次聚合：
select t.date, sum(t.revenue) as revenue, coalesce(sum(e.expense), 0) as expense
from trips t
left join (
select tripid, sum(amount) as expense
from expenses
group by tripid
) e on e.tripid = t.id
group by t.date
我有这两张表；
- 行程
| id | date | revenue |
|---|---|---|
| 1 | 01/01/2020 | 5000 |
| 2 | 01/01/2020 | 3000 |
| 3 | 02/01/2020 | 4000 |
| 4 | 02/01/2020 | 2000 |
- 开支
| id | tripid | amount |
|---|---|---|
| 1 | 1 | 500 |
| 2 | 1 | 300 |
| 3 | 2 | 400 |
| 4 | 2 | 200 |
| 5 | 2 | 700 |
我想获得一天内收取的收入总和和一天内的支出总和。我有以下 sql 结果，但总和完全错误。
SELECT i.id, sum(i.revenue) as total, i.date trip , sum(c.amount) as exp, c.tripid expenses FROM trip i INNER JOIN expenses c ON i.id = c.tripid GROUP BY i.date ORDER BY trip DESC
您可以按行程预聚合费用，然后在外部查询中再次聚合：
select t.date, sum(t.revenue) as revenue, coalesce(sum(e.expense), 0) as expense
from trips t
left join (
select tripid, sum(amount) as expense
from expenses
group by tripid
) e on e.tripid = t.id
group by t.date