/*21. Write a query in SQL to display the country name, city, and number of those departments where at leaste 2 employees
 are working.*/
SELECT country_name,city, COUNT(department_id)  
    FROM countries   
        JOIN locations USING (country_id)   
        JOIN departments USING (location_id)   
WHERE department_id IN   
    (SELECT department_id   
        FROM employees   
     GROUP BY department_id   
     HAVING COUNT(department_id)>=2)  
GROUP BY country_name,city;