[Hacker Rank]Average Population of Each Continent

Given the CITY and COUNTRY tables, query the names of all the continents (COUNTRY.Continent) and their respective average city populations (CITY.Population) rounded down to the nearest integer.

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

Input Format

The CITY and COUNTRY tables are described as follows:

[틀린 쿼리]

SELECT COUNTRY.Continent,ROUND(AVG(CITY.Population))
FROM CITY
INNER JOIN COUNTRY ON CITY.CountryCode= COUNTRY.Code
GROUP BY COUNTRY.Continent

틀린이유: rounded down는 floor

SELECT COUNTRY.Continent,FLOOR(AVG(CITY.Population))
FROM CITY
INNER JOIN COUNTRY ON CITY.CountryCode= COUNTRY.Code
GROUP BY COUNTRY.Continent