How_to_code_subqueries/exercise-06.sql

SELECT vendor_name, vendor_city, vendor_state
FROM vendors
WHERE CONCAT(vendor_state, vendor_city) NOT IN 
    (SELECT CONCAT(vendor_state, vendor_city) as vendor_city_state
     FROM vendors
     GROUP BY vendor_city_state
     HAVING COUNT(*) > 1)
ORDER BY vendor_state, vendor_city