db->prepare("SELECT * FROM users WHERE username = :username LIMIT 1"); $stmt->execute(['username' => $username]); return $stmt->fetch(PDO::FETCH_ASSOC); } public function createUser($username, $password_hash) { $stmt = $this->db->prepare("INSERT INTO users (username, password_hash) VALUES (:username, :pass)"); return $stmt->execute([ 'username' => $username, 'pass' => $password_hash ]); } }