Bolt\Storage\Query\ContentQueryParser::setDirective PHP Method

    public function setDirective($key, $value)
    {
        $this->directives[$key] = $value;
    }

 /**
  * @param ContentQueryParser $contentQuery
  *
  * @return QueryResultset
  */
 public function __invoke(ContentQueryParser $contentQuery)
 {
     $params = $contentQuery->getEntityManager()->createQueryBuilder()->getConnection()->getParams();
     if (strpos($params['driver'], 'mysql') !== false) {
         $contentQuery->setDirective('order', 'RAND()');
     } else {
         $contentQuery->setDirective('order', 'RANDOM()');
     }
     return call_user_func_array($contentQuery->getHandler('select'), [$contentQuery]);
 }