public function getSqlForPriceCategories($sFields = '')
    {
        if (!$sFields) {
            $sFields = 'oxid';
        }
        $sSelectWhere = "select $sFields from " . $this->_getObjectViewName('oxcategories') . " where";
        $sQuotedPrice = \OxidEsales\Eshop\Core\DatabaseProvider::getDb()->quote($this->oxarticles__oxprice->value);

        return "$sSelectWhere oxpricefrom != 0 and oxpriceto != 0 and oxpricefrom <= $sQuotedPrice and oxpriceto >= $sQuotedPrice"
               . " union $sSelectWhere oxpricefrom != 0 and oxpriceto = 0 and oxpricefrom <= $sQuotedPrice"
               . " union $sSelectWhere oxpricefrom = 0 and oxpriceto != 0 and oxpriceto >= $sQuotedPrice";
    }