Question: What are the countries having at least one car maker? List name and id.
Schema: create table car_makers (country varchar, PRIMARY KEY (country)); create table countries (countryname varchar, countryid varchar, PRIMARY KEY (countryname))
SQL: select t1.countryname, t1.countryid from countries as t1 join car_makers as t2 on t1.countryid = t2.country group by t1.countryid having count(*) >= 1