5 10000 50 60000 test.hits SELECT count() FROM test.hits WHERE NOT ignore(rand() % 2 ? URL : Referer) SELECT count() FROM test.hits WHERE NOT ignore(rand() % 2 ? URL : '') SELECT count() FROM test.hits WHERE NOT ignore(rand() % 2 ? SearchPhrase : MobilePhoneModel) SELECT count() FROM test.hits WHERE NOT ignore(rand() % 2 ? '' : PageCharset)