Piwik\Columns\Updater::getUpdatesForDimension PHP Method

    private function getUpdatesForDimension(PiwikUpdater $updater, $dimension, $componentPrefix, $existingColumnsInDb, $conversionColumns = array())
    {
        $column = $dimension->getColumnName();
        $componentName = $componentPrefix . $column;
        if (!$updater->hasNewVersion($componentName)) {
            return array();
        }
        if (array_key_exists($column, $existingColumnsInDb)) {
            if ($dimension instanceof VisitDimension) {
                $sqlUpdates = $dimension->update($conversionColumns);
            } else {
                $sqlUpdates = $dimension->update();
            }
        } else {
            $sqlUpdates = $dimension->install();
        }
        return $sqlUpdates;
    }