public function beforeLoad($m, $q = null)
    {
        if (is_null($q)) {
            return;
        }  // manual load

        if ($this->m2 && $this->m2 != $this->owner->id_field) {
            $q->field($this->m2, $this->m1, $this->short_name);
        } elseif ($this->m2) {
            $q->field($this->f2, $this->fa ?: $this->f1, $this->short_name);
        }
    }