在我的PHP到mysql的数据冗余问题

Question

有人可以查看我的PHP代码吗？如何将我的PHP中的数据冗余修复为mysql？我不希望将相同的数据存储到我的数据库中。谢谢

<?php
$email = "";
$passwords   = "";
$firstname   = "";
$lastname   = "";
$errors = array(); 
$db = mysqli_connect('localhost', 'root', '', 'wdt_assignment');

if (isset($_POST['email'])) {

$email = mysqli_real_escape_string($db, $_POST['email']);
$password = mysqli_real_escape_string($db, $_POST['password']);
$firstname = mysqli_real_escape_string($db, $_POST['firstname']);
$lastname = mysqli_real_escape_string($db, $_POST['lastname']);
if (empty($email)) { array_push($errors, "email is required"); }
if (empty($password)) { array_push($errors, "password is required"); }
if (empty($firstname)) { array_push($errors, "firstname is required"); }
if (empty($lastname)) { array_push($errors, "lastname is required"); }
}

$user_check_query = "SELECT * FROM customer WHERE email='$Email' OR password='$Password' LIMIT 1";
$result = mysqli_query($db, $user_check_query);
$user = mysqli_fetch_assoc($result);
if ($user) { // if user exists
if ($user['email'] === $Email) {
array_push($errors, "email already exists");
}
if ($user['password'] === $Password) {
array_push($errors, "password already exists");
}
}
if (count($errors) == 0) {

$query = "INSERT INTO customer (email, password, firstname, lastname) 
VALUES('$email', '$password', '$firstname','$lastname')";
mysqli_query($db, $query);
$_SESSION['email'] = $email;
$_SESSION['success'] = "You are now logged in";
}
?>

Answer 1

我建议您不要告诉用户这个密码已经存在于数据库中。我附上代码来检查电子邮件是否存在。

<?php
$email = "";
$passwords   = "";
$firstname   = "";
$lastname   = "";
$errors = array();
$db = mysqli_connect('localhost', 'root', '', 'wdt_assignment');
if (isset($_POST['email']))
{
$email = mysqli_real_escape_string($db, $_POST['email']);
$password = mysqli_real_escape_string($db, $_POST['password']);
$firstname = mysqli_real_escape_string($db, $_POST['firstname']);
$lastname = mysqli_real_escape_string($db, $_POST['lastname']);
if (empty($email)) { array_push($errors, "email is required"); }
if (empty($password)) { array_push($errors, "password is required"); }
if (empty($firstname)) { array_push($errors, "firstname is required"); }
if (empty($lastname)) { array_push($errors, "lastname is required"); }
if (count($errors) == 0)
{
$user_check_query = "SELECT * FROM customer WHERE email='$Email' OR password='$Password' LIMIT 1";
$result = mysqli_query($db, $user_check_query);
$affected_rows = mysqli_affected_rows($db);
if ($affected_rows > 0)
{
array_push($errors, "email already exists");
}
else
{
$query = "INSERT INTO customer (email, password, firstname, lastname) 
VALUES('$email', '$password', '$firstname','$lastname')";
mysqli_query($db, $query);
$_SESSION['email'] = $email;
$_SESSION['success'] = "You are now logged in";
}
}
}
?>