MySQL代码只执行一次，而不是在循环中执行多次

Question

<?PHP
session_start();
if (isset($_SESSION['hasVoted']) && $_SESSION['hasVoted'] == '1') {
        print "You've already voted";
    }
else {
    if (isset($_POST['Submit1'])) {
        $ID = $_SESSION['user']; // obtain the ID of the user from the login session
        var_dump($ID);
        $string_results = $_POST['h2'];
        $selected_radio = explode(',', $string_results);
        var_dump($selected_radio);
        $user_name = "root";
        $password = "";
        $database = "surveyTest";
        $server = "127.0.0.1";
        $SQL = "SELECT * FROM tblquestions";
        $db_handle = mysql_connect($server, $user_name, $password);
        $db_found = mysql_select_db($database, $db_handle);
        if ($db_found) {
            $result = mysql_query($SQL);
            $numRows = mysql_num_rows($result); //return number of rows in the table
            var_dump($numRows);
            $qNum = 'q1';
            for ($i = 0; $i < $numRows; $i++)
            {
                var_dump($qNum);
                $_SESSION['hasVoted'] = '1';
                $selected_Value = $selected_radio[$i];
                var_dump($selected_Value);
            //==================================================================================
            //  SET Multiple rows IN THE answers TABLE for each question for a given student.
            //==================================================================================
                $SQL = "INSERT INTO answers (QID, Answer, SID) VALUES ('$qNum', '$selected_Value', '$ID')";
                $result = mysql_query($SQL);
                    $question_Number = ltrim($qNum,'q');
                    $question_Number++;
                    $qNum ='q'.$question_Number;
            }
                mysql_close($db_handle);
                print "Thank you for participating!";
        }
        else {
        print "database error";
        }
    }

    else {
        header("location:login.php");;
    }
}
session_destroy();
?>

<html>
<head>
<title>Process Survey</title>
</head>



<body>

</body>
</html>

当我执行上面的代码时，包含INSERT的$SQL语句只执行一次。这意味着它只向数据库中添加了一条记录。然而，我需要它来添加几个记录到数据库中，这等于$numRows。$qNum和$selected_Value的输出显示了正确的内容。有什么建议吗？

Answer 1

使用$result = mysql_query($SQL) or die(mysql_error());重试

主键在你的桌子上也没问题吗？