SELECT SQL_NO_CACHE COUNT(*) FROM `vse-obru_group`, `vse-obru_ads` WHERE `vse-obru_group`.top_level = '177' AND `vse-obru_ads`.category_id = `vse-obru_group`.bottom_level AND `vse-obru_ads`.info_new = 0 AND (`vse-obru_ads`.city_id = 179 OR `vse-obru_ads`.city_id = -1): Lost connection to MySQL server during query