How to get the user_id from mysql using procedural php?

Question

I am an android/java developer and Im struggling with php. I've made it as far as inserting a new user in the DB, now I want to get their ID.

What do I do with the result? I want to assign it to a variable.

$query = "SELECT user_id FROM users WHERE user_email = '" . $user_email . "'";
$result = 

PS: Im using mysql, not mysqli.

EDIT: Here is what I did:

$query = "SELECT user_id FROM users WHERE user_email = '" . $user_email ."';";
$store_info = mysql_fetch_array(mysql_query($query)); 
$user_id = $store_info['user_id'];
$response["message"] = "User created with id: " . $user_id;
echo json_encode($response);

And the error message after inserting (successfully) the user in the db:

null{"success":3,"message":"User created with id: "}

Answer 1

I assume that your are using MySQLi API

$query = "SELECT user_id FROM users WHERE user_email = '$user_email'"; //Your Query

$store_info = mysqli_fetch_array(mysqli_query($connection, $query)); 
//Execute the query, fetch the result, it's just one result so no need for a while loop

echo $store_info['user_id']; //echo id

---

As per the comments, you requested a mysql_() version so here you go...

$query = "SELECT user_id FROM users WHERE user_email = '$user_email'"; //Your Query

$store_info = mysql_fetch_array(mysql_query($query)); 
//Execute the query, fetch the result, it's just one result so no need for a while loop

echo $store_info['user_id']; //echo id

Still consider using mysqli_() or PDO instead. Why? Because mysql_() is now deprecated, read the red box on the documentation page which says...

Refer this answer for PDO tutorial

Answer 2

Here is the PDO variant:

<?php
//credentials
$host = 'localhost';
$user = "user";
$password = '';
$db_name = 'test';
$port = 3306;

//connection to the database
try
{
    $connection = new PDO("mysql:host=$host;port=$port;dbname=$db_name", $user, $password);
    $connection->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
}
catch (PDOException $e)
{
    echo 'Connection failed: ' . $e->getMessage();
}

//prepare and execute SELECT statement
$sth = $connection->prepare("SELECT user_id FROM users WHERE user_email = :email");
$sth->execute(array(':email' => $user_email));

$record = $sth->fetch(PDO::FETCH_ASSOC);
print $record["user_id"];