Not getting the expected user information - php

Question

I'm trying to make an admin page and allow only users with role 2 for some reason its not giving me the information I expected.
<?php
session_start();
require_once('includes/mysql_config.php');
$id = isset($_SESSION['id']) ? $_SESSION['id'] : header('location: login.php');
$user = mysqli_query($con, "SELECT * FROM users WHERE id =".$_SESSION['id']) || false;
if($user['role'] == '2'){
echo "Hello $user['name']";
}
else {
header('location: index.php');
}
?>
When I do vardump($user) its giving me the output 1.
When I echo the $_SESSION['id'] it is giving me the right id (the session id is the same as user id).

Answer 1

Right now what you have done is, you just executed the query and had the resultset stored in $user. You need to fetch the results from the Result Set.
$user = mysqli_fetch_array($user);
Now it should work as expected.
Update: You should also handle the following:
Sanitization: Make sure you use ' for the values and ` for the column names. Also use mysqli_real_escape_string() for escaping some obvious stuff.
Validation: That's the next most important. Try checking if the resultset has any rows returned. You can do by using mysqli_num_rows($user) > 0 or precisely in your case, mysqli_num_rows($user) == 1.
Variables: Here in the example, I have used the same $user for the Result Set as well as the row. It is always better to have two separate variables, say, $userRes (for result set) and $userData (for the fetched data).
Hope this should answer your question.

Answer 2

After a successful select query mysqli_query() will return an mysqli_result object. You have to itterate over that to get your results. For example:
$user = mysqli_query($con, "SELECT * FROM users WHERE id =".$_SESSION['id']) || false;
if(user ){
// Cycle through results
while ($row = user ->fetch_object()){
$users[] = $row;
}
$user->close();
}

Answer 3

You're not fetching the results... If you check the manual, and look for the return value of mysqli_query(), you'll find:
Returns FALSE on failure. For successful SELECT, SHOW, DESCRIBE or
EXPLAIN queries mysqli_query() will return a mysqli_result object. For
other successful queries mysqli_query() will return TRUE
So go ahead and fetch it:
//$user = mysqli_query($con, "SELECT * FROM users WHERE id =".$_SESSION['id']) || false; // I'm unfamiliar with this || false stuff.
$result = mysqli_query($con, "SELECT * FROM users WHERE id =".$_SESSION['id']);
$user = mysqli_fetch_array($result);
It's also a good idea to sanitize your input (in order to prevent SQL-injection) and to check whether there are any results with mysqli_num_rows().