如何将此警告移至此php脚本

Question

我有这个php查询，它将许多表从(婴儿类到标准的7级)连接起来，这样我就可以得到每个表的总和表和。

但是当我运行这个查询时，它会给我一个警告：

Warning: mysql_fetch_array() expects   
parameter 1 to be resource, boolean given in   
C:\wamp\www\db_valentine_V2\Templates\school_income.php on line 872

我想在第872行中找出有这个脚本的地方

while($res=mysql_fetch_array($q)){

有人能帮我移除这个警告吗?它真的花了我很长时间，没有任何成功。

  <?php

 $date="date";
 $class="class";
 $database=("mcl");
 mysql_connect("localhost","root","mcl");
 @mysql_select_db(mcl) or die( "Unable to select database");


if(isset($_REQUEST['submit'])){
$class=$_POST['class'];
$date=$_POST['date'];


$sql="SELECT SUM(Total) FROM 
    ( SELECT     
   SUM(school_fee+trans_fee+reg_fee+edutrip_fee+stationery_fee+food_fee+
  uniform_fee+sport_uniform) As Total FROM payment UNION  

    SELECT SUM(school_fee+trans_fee+reg_fee+edutrip_fee+stationery_fee+
   food_fee+uniform_fee+sport_uniform) As Total FROM payment_one UNION
  SELECT    SUM(school_fee+trans_fee+reg_fee+edutrip_fee+stationery_fee+food_fee
  +uniform_fee+sport_uniform) As Total   
        FROM payment_two UNION
   SELECT   SUM(school_fee+trans_fee+reg_fee+edutrip_fee+stationery_fee+food_fee
  +uniform_fee+sport_uniform) As Total   
        FROM payment_three UNION
  SELECT   
 SUM(school_fee+trans_fee+reg_fee+edutrip_fee+stationery_fee+food_fee+
 uniform_fee+sport_uniform) As Total   
        FROM payment_four UNION
  SELECT SUM(school_fee+trans_fee+reg_fee+edutrip_fee+stationery_fee+food_fee+
  uniform_fee+sport_uniform) As Total   
        FROM payment_five UNION
 SELECT   SUM(school_fee+trans_fee+reg_fee+edutrip_fee+stationery_fee+food_fee+
 uniform_fee+sport_uniform) As Total   
        FROM payment_six UNION
 SELECT SUM(school_fee+trans_fee+reg_fee+edutrip_fee+stationery_fee+food_fee+
 uniform_fee+sport_uniform) As Total   
        FROM payment_seven )a)";


 $q=mysql_query($sql);  

    }

  ?>


<form method="post">
<table width="500" border="0">
 <tr>
<td>Class</td>
<td><input type="text" name="class" value="<?php echo $class;?>" /></td>

<td>Year</td>
<td><input type="number" name="date" value="<?php echo $date;?>" /></td>

<td><input type="submit" name="submit" value="Search" /></td>
 </tr>
</table>
<br />
   </form>
    <table>
    <h4>
   This is total amount of money payed by&nbsp;<?php echo $class;?> &nbspclass     
   in&nbsp<?php echo $date;?>&nbsp;</h4><hr> 
   <table width="700" border="0" height="2" cellpadding="0" cellspacing="1" >
   <tr>
    <td bgcolor="#FF9900" width="50">Class</td>
     <td bgcolor="#FF9900" width="300">Total amount of money payed</td>

   </tr>
  <?php
   while($res=mysql_fetch_array($q)){

       ?>

     <tr>
     <td width="100"><?php echo $res['class'];?></td>
     <td width="200"><?php echo $res['SUM(Total)'];?></td>

     </tr>

    <?php }?>    



     </table>          

Answer 1

尝试：

while(!empty($q) and $res=mysql_fetch_array($q)){

Answer 2

在您的代码变量中，$q没有在if条件之外访问的范围。

因此，您需要在您的if条件之前定义它。将下面的行添加到if条件之上。

$q="";

代替while循环，请使用以下代码：

if(!empty($q)) {
   while($res=mysql_fetch_array($q)){
           -----------
          your code
          ---------------
   }
}

Answer 3

试试像这样的东西

if($q === FALSE) {
        die(mysql_error()); // TODO: better error handling
    }

while($res=mysql_fetch_array($q))
{
    //do here
}