PHP/MySQL 删除记录不会删除


PHP/MySQL Delete Record doesn't Delete

这简直让我发疯了!我有一个名为课程列表的网页,我正在使用PHP创建一个HTML表格,列出存储在MySQL数据库中的课程(使用Wampserver)

<?php
require "dbconn.php";
$query = "SELECT coursecode, coursename FROM course";
$results = $connect->query($query);
$numrow = $results->num_rows;
?>
<html>
  <head></head>
    <body>
      <table border="1">
        <?php
        $count = 0;
        while ($count < $numrow)
            {
                $row = $results->fetch_assoc();
                extract($row);
                echo "<tr>";
                echo "<td>";
                echo "<a href='updatecourseform.php?coursecode=".$coursecode."'>".$coursecode."</a>";
                echo "<td>";
                echo $row['coursename'];
                echo "</td>";
                echo "<td>";
                echo "<a href='deletecourse.php?coursecode=".$coursecode."'>Delete</a>";
                echo "</td>";
                echo "</tr>";
                $count = $count + 1;
            }
        ?>
        </table>
        <br />
        The number of courses found was: <?php echo $numrow; ?>
        <br /><br />
        Click <a href="addcourse.html">here</a> if you want to add a Course
    </body>
</html>

这将打印出一个漂亮的 HTML 表格,其中包含所有正确数据,右侧有一行带有单词 Delete 这是一个超链接,应该允许我删除课程。但是当我单击"删除"时,它不会删除!这是我的删除课程.php。

<?php
require "dbconn.php";
$coursecode = $_GET['coursecode'];
$query = "DELETE FROM course WHERE coursecode =".$coursecode;
$results = $connect->query($query);
header("Location: courselisting.php");
?>

这非常令人沮丧,因为我有完全相同的示例适用于不同的数据库......我刚刚切换了所有变量名称,但本质上逻辑和语法以及一切都是一样的!

单引号括起来,如下所示:

$query = "DELETE FROM course WHERE coursecode='" . $coursecode . "'";
$query = "DELETE FROM course WHERE coursecode='{$coursecode}'";