private function getVisitFieldsToUpdate(array $row, $location)
    {
        if (isset($location[LocationProvider::COUNTRY_CODE_KEY])) {
            $location[LocationProvider::COUNTRY_CODE_KEY] = strtolower($location[LocationProvider::COUNTRY_CODE_KEY]);
        }

        $valuesToUpdate = array();
        foreach (self::$logVisitFieldsToUpdate as $column => $locationKey) {
            if (empty($location[$locationKey])) {
                continue;
            }

            $locationPropertyValue = $location[$locationKey];
            $existingPropertyValue = $row[$column];

            if (!$this->areLocationPropertiesEqual($locationKey, $locationPropertyValue, $existingPropertyValue)) {
                $valuesToUpdate[$column] = $locationPropertyValue;
            }
        }
        return $valuesToUpdate;
    }