mysql - 每个日期的 SQL 总和

Question

我有一个名为“租金”的表，我在其中存储如下数据:

id | rent_id | start_date | end_date  | amount
---------------------------------------------
1  |   54    | 12-10-2019 | 26-10-2019| 100
2  |   54    | 13-10-2019 | 20-10-2019| 150

我期望什么？结果如下:

12-10-2019 , amount 100
from 13-10-2019 to 20-10-2019, amount 250
from 21-10-2019 to 26-10-2019, amount 100

基本上我想要每一天的金额总和。但我也想计算“之间的天数”。

所以预期的结果是:

    id | rent_id | day        |  amount
    ---------------------------------------------
    1  |   54    | 12-10-2019 | 100
    2  |   54    | 13-10-2019 | 250
    3  |   54    | 14-10-2019 | 250

等等……

我实际上正在运行以下 sql:

select start_date, ( select sum(amount) from rentals as t2 where t2.start_date <= t1.start_date) as amount from rentals as t1 WHERE rent_id = 54 group by start_date

但结果并不像预期的那样......

我正在使用 MySQL。

Answer 1

我认为这可能有帮助 使用 MSSQL

declare @startDate date ='11 Oct 2019'
declare @endDate date ='30 Oct 2019'
declare @rentId nvarchar(50)='54'


select d.Day,d.rent_id,isnull(d.amount,0) as amountPaid, amount = SUM(d.amount) OVER (ORDER BY d.Day) from (
select c.Day,c.id,case when rent_id is null then @rentId else rent_id end as rent_id,c.amount  from (
select * from (
SELECT DATEADD(DAY,number+1,@startDate) [Day]
FROM master..spt_values
WHERE type = 'P'
AND DATEADD(DAY,number+1,@startDate) < @endDate
) a left join (select * from rentals where rent_id=@rentId) b on a.[Day] = b.start_date) c) d