Doctrine\DBAL\Query\QueryBuilder::getQueryPart PHP Method

    public function getQueryPart($queryPartName)
    {
        return $this->sqlParts[$queryPartName];
    }

 /**
  * Returns the sql expression to determinate the distincts numbers of lines
  *
  * @return string
  */
 protected function getDistinct()
 {
     if (isset($this->conf->group)) {
         return $this->conf->group;
     }
     return implode(', ', $this->queryBuilder->getQueryPart('select'));
 }