Sql, nested select

Question

I am learning how to do a select inside another select and I came with a solution, but it is too long. Can this solution be shorter?

I would like this query:

    select continent, name 
from world x
where name =
    (SELECT min(name) FROM world
        WHERE continent = 'Africa')
or name =
    (SELECT min(name) FROM world
        WHERE continent = 'Asia')
or name =
    (SELECT min(name) FROM world
        WHERE continent = 'Caribbean')
or name =
    (SELECT min(name) FROM world
        WHERE continent = 'Eurasia')
or name =
    (SELECT min(name) FROM world
        WHERE continent = 'Europe')
or name =
    (SELECT min(name) FROM world
        WHERE continent = 'North America')
or name =
    (SELECT min(name) FROM world
        WHERE continent = 'Oceania')
or name =
    (SELECT min(name) FROM world
        WHERE continent = 'South America')
order by continent
limit 8

To be writen in a way like this:

    SELECT continent, name, area FROM world x
  WHERE area >= ALL
    (SELECT max(area) FROM world y
        WHERE y.continent = x.continent
          AND area > 0)

Can also anyone explain the second query, how it works, thanks.

Answer 1

Try This

SELECT Continent, Name 
FROM World x
WHERE NAME IN (SELECT MIN(Name) FROM world WHERE Continent IN ('Africa', 'Asia', 'Caribbean', 'Eurasia', 'Europe', 'North America', 'Oceania', 'South America') GROUP BY Continent)
ORDER BY Continent
LIMIT 8