Script not getting values from the database [duplicate] - php

Question

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What to do with mysqli problems? Errors like mysqli_fetch_array(): Argument #1 must be of type mysqli_result and such
(1 answer)
Closed 2 years ago.
i have this user sign in script using php prepared statement, but it is not working i have tried to switch values but still not working sometimes i get a "user does not exit" error sometimes just a blank page with the redirected link.
if(isset($_POST['login'])){
require 'dbh.php';
$mail = $_POST['email'];
$pwd = $_POST['password'];
if (empty($mail) || empty($pwd)) {
header("Location: ../login.php?error=empty");
exit();
} else {
$sql = "SELECT * FROM users WHERE id=? OR email=?;";
$stmt = mysqli_stmt_init($db);
if (!mysqli_stmt_prepare($stmt, $sql)) {
header("Location: ../login.php?error=error");
exit();
} else {
mysqli_stmt_bind_param($stmt, "ss", $mail, $pwd);
mysqli_stmt_execute($stmt);
$result = mysqli_stmt_get_result($stmt);
if ($row = mysqli_fetch_assoc($result)){
$pwdCheck = password_verify($pwd, $row['password']);
if($pwdCheck == false) {
header("Location: ../login.php?error=wrongPassword");
exit();
} else if ($pwdCheck == true) {
session_start();
$_SESSION['uId'] = $row['id'];
$_SESSION['username'] = $row['username'];
header("Location: ../profile/index.php?success");
exit();
}
}
}
}
} else {
header("Location: ../login.php");
exit();
} ```

Answer 1

I can see many mistakes in your code.
seems like you have missed entering the id param in the query.
Here you have mentioned id & email, "SELECT * FROM users WHERE id=? OR email=?;"
But here (mysqli_stmt_bind_param($stmt, "ss", $mail, $pwd);) you are binding $mail and password and not id and email.
You have used a extra semi colon ($sql = "SELECT * FROM users WHERE id=? OR email=?;";)