Question

嗨大家我一直在编码并且不能很好地解决这个问题...... 样品：从BILLING表中可以看到2张账单，费用分别为1月1,500和2月2,000 从PAYMENT表中，客户支付了2,000，这笔金额应扣除到1月BILL和2月账单，因为2,000比1月的金额大，所以应该自动扣除500到下一个BILL 2月左右。表

OUT PUT

AMOUNT PAID - 2,000

| MONTH     |   BILL    |    AMT PAID   |   BALANCE   |
-------------------------------------------------------
| January   |   1,500   |    2,000      |     -500    |
| February  |   2,000   |      500      |    1,500    |

QUERY

SQL BILLING
| MONTH | BILL  |
| JAN   | 1500  |
| FEB   | 2000  | 
$query = SELECT MONTH, BILL FROM billing
$amt_paid = 2000;
foreach($query as $row){
   $actual_paid = $amt_paid;
   $actual_bal -= $actual_paid;
   echo '<tr>';
   echo '<td>'.$row->MONTH.'</td>';
   echo '<td>'.$row->BILL.'</td>';
   echo '<td>'.$actual_paid.'</td>';
   echo '<td>'.$actual_bal.'</td>';
}

WRONG RESULT
| MONTH     |   BILL    |    AMT PAID   |   BALANCE   |
-------------------------------------------------------
| January   |   1,500   |    2,000      |     -500    |
| February  |   2,000   |    2,000      |        0    |

我想要显示确切的金额和余额。请帮忙，我希望你能猜出我的意思：D

Answer 1

- 您的表格中应该有monthIndex或datetime

select t0.MONTHNAME, t0.bill, t0.pay, (select sum(bill - pay) from billing t1 where t1.MONTHINDEX <= t0.MONTHINDEX) bal
from billing t0

使用PHP SQL从账单中扣除金额

1 个答案: