Question

I’ve got a table bbc with the following columns:

• name (refers to a name of a country within a particular region of the world)
• region (continent of the world)
• population (population of the country in the name name field)

The question I’m trying to answer:

Find each country that belongs to a region where all populations are less than 250000000. Show name, region and population.

I was thinking the answer might be something like:

SELECT name, region, population 
FROM bbc 
GROUP by region 
HAVING MAX(population) < 250000000 

I get the feeling I am way off course with this answer… any help would be appreciated!

Answer 1

select b.name, b.region, b.population
from bbc as b
where
    b.region in
    (
        select t.region
        from bbc as t
        group by t.region
        having max(t.population) < 25000000
    )