try {
    $f3->set('DB', new \DB\SQL(
        "mysql:host={$f3->get('db.host')};port={$f3->get('db.port')};dbname={$f3->get('db.name')}",
        $f3->get('db.user'),
        $f3->get('db.pass')
    ));

} catch (Exception $e) {
    echo 'Caught exception: ', $e->getMessage(), "\n";
    return null;
}