[hackerrank] African Cities

[hackerrank] Prepare > SQL > Aggregation > African Cities

 

[문제]

Given the CITY and COUNTRY tables, query the names of all cities where the CONTINENT is 'Africa'.

Note: CITY.CountryCode and COUNTRY.Code are matching key columns.

Input Format

The CITY and COUNTRY tables are described as follows: 

 

[MYSQL]

 

 

[ORCALE]

 

    select a.name
    from city a inner join country b on (a.countrycode = b.code)
    where continent = 'Africa';