Question

当billpay字段没有“付款”值时，我的以下条件无法正常工作。然后，首先“if”现在显示表中102美元的任何数据，它只是显示空白单元格。

if($f1022 ==0){
   echo $f102;  
}
 else {
   echo $fpending = $f102 - $f1022;
}

我也尝试过如下，但结果相同，

if(empty($f1022)){
  echo $f102;   
}
else {
  echo $fpending = $f102 - $f1022;
}

和

     if($f1022 ==0){
       echo $f102;  
       }
       else {
     echo $fpending = $f102 - $f1022;
      }

下面是带有html表的完整脚本。

<html>
<head>
<style>
table, td, th {    
border: 1px solid #ddd;
text-align: left;
 }

table {
border-collapse: collapse;
 }

 th, td {
padding: 15px;
}
 </style>
 </head>
<body> 
<table width="700px" id="workweek" class="wwtable"> 
 <tbody> 
 <tr>
 <th>Supplier</th>
 <th>Bill</th>
 <th>Payment</th>
 <th>Due</th>
 </tr>

<?php
error_reporting(1);
$conn = mysqli_connect("127.0.0.1","root","","mehrazin");

  $detailss81s = "SELECT *, SUM(acamount) AS sum FROM account WHERE billpay 
   = 
'bill' GROUP BY factsuply ";
  $details_results81s = mysqli_query($conn,$detailss81s)
   or die ( "Couldn't get Products: ".mysqli_error($conn) );
   while ( $det_row = mysqli_fetch_array ( $details_results81s ) )
     {//===1st
     $f101 = $det_row[ 'factsuply' ];
   $f102 = $det_row[ 'sum' ];   
     ?>
    <tr>
<td width="400px"><?php echo "$f101"; ?></td>
<td width="100px"><?php echo "$f102"; ?></td>
   <?php
   $detailss81ss = "SELECT *, SUM(acamount) AS sum FROM account WHERE 
 factsuply 
= '$f101' AND billpay = 'payment' GROUP BY factsuply ";
$details_results81ss = mysqli_query($conn,$detailss81ss)
or die ( "Couldn't get Products: ".mysqli_error($conn) );
while ( $det_rows = mysqli_fetch_array ( $details_results81ss ) )
    {//===2nd
  $f1022 = $det_rows[ 'sum' ];  

  ?>
 <td width="100px"><?php  echo "$f1022"; ?></td>
  <td width="100px"><?php 

  if($f1022 ==0){
  echo $f102;   
   }
   else {
  echo $fpending = $f102 - $f1022;
   }

  ?></td>

  <?php  
  }//===2nd 
  }//===1st
   ?>
 </tr>  

 </tbody>
</table>
</body> 
</html>

Answer 1

我认为您的查询是问题的根本原因。就目前而言，ent410373条款可能完全丢弃某些不匹配的WHERE组。解决此问题的一种方法是在整个表上使用条件聚合：

factsuply

顺便说一句，与SELECT factsuply, SUM(CASE WHEN billpay = 'bill' THEN acamount ELSE 0 END) AS sum FROM account GROUP BY factsuply;一起做SELECT *通常是件坏事。在您的特定情况下，MySQL容忍它，它甚至似乎不会导致您的问题。但是你应该知道这个查询甚至不会在大多数其他数据库上运行。

当在Mysql表中没有付款时，从php中的账单中减去付款

1 个答案: