今天我为我的一个客户发布了一个新的应用程序，insert语句出现了一些不正常的情况。在测试过程中，我们没有遇到类似的情况，我不确定这是因为很多用户同时访问（100个用户），还是与其他内容有关。因此，在1 insert之后，它在数据库表中插入了1条记录，其他一些2-3个重复项…我没有使用事务，这是否可以解决这个问题？下面您可以找到我的代码和带有事务的代码，以防这是解决方案。非常感谢你的帮助！

$submit_the_bill = "INSERT INTO bill_status
(`bill_status_bill_id`,`bill_status_username`, `bill_status_phone_number`, `bill_status_status`,`bill_paid`, `deduction`)
VALUES ('".$bill_id."', '".$_SESSION['username']."', '".$_SESSION['phone_number']."','1','0','".$deduction."')";
$submit_the_bill_result = $conn->query($submit_the_bill);

//TRANSACTION STARTS HERE
try {
$conn->autocommit(FALSE);
$submit_the_bill = "INSERT INTO bill_status
(`bill_status_bill_id`,`bill_status_username`, `bill_status_phone_number`, `bill_status_status`,`bill_paid`, `deduction`)
VALUES ('".$bill_id."', '".$_SESSION['username']."', '".$_SESSION['phone_number']."','1','0','".$deduction."')";
$submit_the_bill_result = $conn->query($submit_the_bill);
$conn->commit();
} catch (Exception $e) {
// An exception has been thrown
// We must rollback the transaction
$conn->rollback();
}

这是一个完整的页面，信息来自一个表单的前一个页面，在执行查询并发送电子邮件后进入主页。有什么想法吗？

<?php session_start();

require('include/config.php'); //database connection

require "PHPMailer/PHPMailerAutoload.php";

$bill_id = $_POST['bill_id'];
$user_phone_number = $_POST['user_phone_number'];
$deduction = $_POST['deduction'];

$net_value_hidden = round($_POST['net_value_hidden'],2);
$official_cost_hidden = round($_POST['official_cost_hidden'],2);
$personal_cost_hidden = round($_POST['personal_cost_hidden'],2);
$tax_hidden = round($_POST['tax_hidden'],2);
$total_hidden = round($_POST['total_hidden'],2);
$total_private_price_with_vat = ($personal_cost_hidden/100)*20;
$total_private_price_with_vat = round($total_private_price_with_vat,2);
$total_payable_ammount = round($personal_cost_hidden + $total_private_price_with_vat,2);

if($total_hidden == 0) {$deduction = 4;}

if($deduction == 1) {$deduction_email = "Salary";}
else if($deduction == 2) {$deduction_email = "Cash";}
else if($deduction == 3) {$deduction_email = "Bank Transfer";}
else {$deduction_email = "No deduction";}

$submit_the_bill = "INSERT INTO bill_status
(`bill_status_bill_id`,`bill_status_username`, `bill_status_phone_number`, `bill_status_status`,`bill_paid`, `deduction`)
VALUES ('".$bill_id."', '".$_SESSION['username']."', '".$_SESSION['phone_number']."','1','0','".$deduction."')";
$submit_the_bill_result = $conn->query($submit_the_bill);

$sql_smtp = "SELECT * FROM smtp_settings";
$result_smtp = $conn->query($sql_smtp);
if ($result_smtp->num_rows > 0) {   
    while($row = $result_smtp->fetch_assoc()) {
        $smtp_host = $row['smtp_server'];
        $smtp_username = $row['smtp_user_email'];
        $smtp_password = $row['smtp_user_password'];
        $smtp_ssl = $row['smtp_ssl'];
        $smtp_port = $row['smtp_port'];
    }
}
if ($smtp_ssl == 1) {$smtp_ssl = "ssl";} else {$smtp_ssl = "tls";}

$mail = new PHPMailer;

$mail->isSMTP();                                      // Set mailer to use SMTP
$mail->Host = $smtp_host;  // Specify main and backup SMTP servers
$mail->SMTPAuth = true;                               // Enable SMTP authentication
$mail->Username = $smtp_username;                 // SMTP username
$mail->Password = $smtp_password;                           // SMTP password
$mail->SMTPSecure = $smtp_ssl;                            // Enable TLS encryption, `ssl` also accepted
$mail->Port = $smtp_port;                                    // TCP port to connect to

$mail->setFrom('email@example.com', 'Email');
$mail->addAddress($_SESSION['username']);               // Name is optional
$mail->isHTML(true);                                  // Set email format to HTML

$mail->Subject = $_SESSION['username']." submitted new bill - ".$_SESSION['bill_period'];
$mail->Body    = $_SESSION['username']."(".$_SESSION['phone_number'].") Submit New Bill - ".$_SESSION['bill_period']." <br/><br/>";

$mail->AltBody = $_SESSION['username']."(".$_SESSION['phone_number'].") Submit New Bill - ".$_SESSION['bill_period']." <br/><br/>";

if(!$mail->send()) {
    echo 'Message could not be sent.';
    echo 'Mailer Error: ' . $mail->ErrorInfo;
} else {
    //echo 'E-mail sent';
}
unset($_SESSION['bill_period']);
$conn->close();

header("Location:location"); //going to the home page

?>