Uppdatera (skrivfel korrigerade):
SELECT city,state,
CASE
WHEN (city IS NULL OR city='') AND (state IS NULL or state='') THEN ''
ELSE country
END as country_1
FROM `table`
Du kan också använda IF
istället för CASE
:IF ((city IS NULL OR city='') AND (state IS NULL or state=''),'',country) as country_1