if($_POST["submit"]) { $user_id = $_SESSION["user_id"]; $name = $_POST["name"]; $email = $_POST["email"]; $contact_number = $_POST["contact_number"]; $sql = "UPDATE users SET name='$name', email='$email', contact_number='$contact_number' WHERE id='$user_id'"; $result = mysqli_query($db, $sql); if($result) { echo "User information updated successfully!"; } else { echo "Error updating user information!"; } }This code updates the user's name, email, and contact number in the website's database using SQL. The `mysqli_query()` function is used to execute the SQL statement, and the result of the query is checked to determine if the update was successful or not. The package library used in this code is MySQLi, which is a PHP extension that provides an interface for accessing MySQL databases.