code: public function findVariantBase($objFilter)
      {
          $objNewFilter = $this->copyFilter($objFilter);
  
          $idList = $this
              ->getConnection()
              ->createQueryBuilder()
              ->select('id')
              ->from($this->getTableName())
              ->where('varbase=1')
              ->execute()
              ->fetchAll(\PDO::FETCH_COLUMN);
  
          $objNewFilter->addFilterRule(new StaticIdList($idList));
          return $this->findByFilter($objNewFilter);
      }
docs: {@inheritdoc}