framework/caching/DbQueryDependency.php
private function executeQuery($query, $db)
    {
        if ($this->method === null) {
            return $query->one($db);
        }
        if (is_string($this->method)) {
            return call_user_func([$query, $this->method], $db);
        }

        return call_user_func($this->method, $query, $db);
    }
private function executeQuery($query, $db)
    {
        if ($this->method === null) {
            return $query->one($db);
        }
        if (is_string($this->method)) {
            return call_user_func([$query, $this->method], $db);
        }

        return call_user_func($this->method, $query, $db);
    }
Executes the query according to [[method]] specification.
@param QueryInterface $query query to be executed.
@param mixed $db connection.
@return mixed query result.