[SQL][HackerRank] Revising Aggregations - The Sum Function

https://www.hackerrank.com/challenges/revising-aggregations-sum/problem?h_r=next-challenge&h_v=zen

Revising Aggregations - The Sum Function | HackerRank

Query the total population of all cities in CITY where District is California.

Input Format

The CITY table is described as follows:

• query total population ==> SELECT SUM(POPULATION)
• in CITY table ==> FROM CITY
• District is California ==> WHERE DISTRICT = ‘California’

SELECT SUM(POPULATION)
FROM CITY
WHERE DISTRICT = 'California';