这是我目前的代码：

public function index()
{
    $tbl = 'm_trx';
    $db = \Config\Database::connect();
    $builder = $db->table($tbl);
    
    $data = [];

    $cols = "{$tbl}.*";
    $builder->select($cols);

    $data = $builder->get()->getResult();
    $asd = [
        'message' => $builder->getLastQuery(),
        'data' => $data,
    ];
    return $this->respond($asd);
}

但它返回错误
"message": "Call to undefined method CodeIgniter\\Database\\MySQLi\\Builder::getLastQuery()",
如果我将$builder->getLastQuery()更改为$builder->db->getLastQuery()，它将返回此错误
"message": "Cannot access protected property CodeIgniter\\Database\\MySQLi\\Builder::$db",