SELECT firstSignificantSubdomain('http://hello.canada.ca') AS canada, firstSignificantSubdomain('http://hello.congo.com') AS congo, firstSignificantSubdomain('http://pochemu.net-domena.ru') AS why; SELECT firstSignificantSubdomain('ftp://www.yandex.com.tr/news.html'), firstSignificantSubdomain('https://www.yandex.ua/news.html'), firstSignificantSubdomain('magnet:yandex.abc'), firstSignificantSubdomain('ftp://www.yandex.co.uk/news.html'), firstSignificantSubdomain('ftp://yandex.co.yandex'), firstSignificantSubdomain('http://ввв.яндекс.org.рф'), firstSignificantSubdomain('https://api.www3.static.dev.ввв.яндекс.рф'); SELECT firstSignificantSubdomain('http://hello.canada.c'), firstSignificantSubdomain('http://hello.canada.'), firstSignificantSubdomain('http://hello.canada'), firstSignificantSubdomain('http://hello.c'), firstSignificantSubdomain('http://hello.'), firstSignificantSubdomain('http://hello'), firstSignificantSubdomain('http://'), firstSignificantSubdomain('http:/'), firstSignificantSubdomain('http:'), firstSignificantSubdomain('http'), firstSignificantSubdomain('h'), firstSignificantSubdomain('.'), firstSignificantSubdomain(''), firstSignificantSubdomain('http://hello.canada..com'), firstSignificantSubdomain('http://hello..canada.com'), firstSignificantSubdomain('http://hello.canada.com.');