public function check_mysql() {
        try {
            $result = DB::selectOne('SELECT 1 AS n');
            if ($result->n != 1) { throw new Exception("Unexpected Database Connection Result", 1); }
            return ['up' => true, 'note' => null];
        } catch (Exception $e) {
            Log::warning("Database Connection Failed: ".$e->getMessage());
            $note = $e->getMessage();
            return ['up' => false, 'note' => $note];
        }
    }