php - fatal error : Uncaught exception 'PDOException' with message 'SQLSTATE[HY000]: General error' . 。 C :\xampp\. .PDOStatement->fetch().. 第 83 行

Question

我实际上已经看到过关于“ fatal error :未捕获的异常'PDOException'”的类似问题。

但是我无法使用我所看到的来解决我所面临的挑战。

下面是代码和错误消息

<?php 
$sql5 = " set @rownum := 0; 
set @sum := 0;

select DISTINCT(ROUND(the_avg,4))
 FROM (
    select water_level, 
@rownum := (@rownum + 1) as rownum, 
@sum := IF(@rownum mod 7 = 1,0 + water_level,@sum + water_level) as running_sum,
IF(@rownum mod 7 = 0,@sum / 7,NULL) as the_avg
FROM " .$table." WHERE record_month_year = '".$startDateReport."'
order by id ASC
) s ";
$result5 = $db->prepare($sql5);
$result5->execute();
while ($rowReport = $result5->fetch(PDO::FETCH_ASSOC)) {
    ?>
    <tr style="font-size:11px;">
        <td><?php echo $rowReport['the_avg'] ; ?></td>
        </tr>
        <?php 
        }
        ?>

第 83 行是:

while ($rowReport = $result5->fetch(PDO::FETCH_ASSOC)) {

错误:

Fatal error: Uncaught exception 'PDOException' with message 'SQLSTATE[HY000]: General error' in C:\xampp\htdocs\awos\includes\loadboreholedatareport.php:83 Stack trace: #0 C:\xampp\htdocs\awos\includes\loadboreholedatareport.php(83): PDOStatement->fetch() #1 C:\xampp\htdocs\awos\borData-report.php(46): include('C:\xampp\htdocs...') #2 {main} thrown in C:\xampp\htdocs\awos\includes\loadboreholedatareport.php on line 83.

Answer 1

使用 PDO 一次只能执行一个查询.. 单独执行它们，就像这样..

   $db->query("set @rownum := 0"); 
    $db->query("set @sum := 0");
    $sql5 = "select DISTINCT(ROUND(the_avg,4))
     FROM (
        select water_level, 
    @rownum := (@rownum + 1) as rownum, 
    @sum := IF(@rownum mod 7 = 1,0 + water_level,@sum + water_level) as running_sum,
    IF(@rownum mod 7 = 0,@sum / 7,NULL) as the_avg
    FROM " .$table." WHERE record_month_year = '".$startDateReport."'
    order by id ASC
    ) s ";

其余的都是一样的。