[SQL][HackerRank] Asian Population

https://www.hackerrank.com/challenges/asian-population/problem

Asian Population | HackerRank

Given the CITY and COUNTRY tables, query the sum of the populations of all cities where the CONTINENT is 'Asia'.

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

Input Format

The CITY and COUNTRY tables are described as follows:

• join two tables on countrycode ==> FROM CITY AS i JOIN COUNTRY AS o ON i.COUNTRYCODE=o.CODE
• query sum of populations of cities ==> SELECT SUM(i.POPULATION)
• where Continent is ‘Asia’ ==> WHERE o.CONTINENT=‘Asia’

      

      

      

    
    

      <sql />
    
SELECT SUM(C.POPULATION)
FROM CITY AS C
JOIN COUNTRY AS O ON C.COUNTRYCODE = O.CODE
WHERE O.CONTINENT = 'Asia';