sql notes: hackerrank japan population

Problem

Query the sum of the populations for all Japanese cities in CITY. The COUNTRYCODE for Japan is JPN.

Input Format
The CITY table is described as follows:

Analysis

• query sum of population ==> SELECT SUM(POPULATION)
• in CITY table ==> FROM CITY
• Japanese cities ==> WHERE COUNTRYCODE = ‘JPN’

Solution

1

SELECT SUM(POPULATION) FROM CITY WHERE COUNTRYCODE = 'JPN';

Link

Japan Population
(中文版) SQL 笔记: Hackerrank Japan Population