SQL 문제풀이
[해커랭크 SQL] Aggregation - Japan Population
냄비짱
2023. 8. 23. 00:23
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❓ Question
https://www.hackerrank.com/challenges/japan-population
Japan Population | HackerRank
Query to the sum of the populations of all Japanese cities in CITY.
www.hackerrank.com
❗ Answer
SELECT SUM(population)
FROM city
WHERE countrycode = 'JPN';
📌 Discussion
- where 절에서 조건에 맞는 레코드만 추출 후 sum 집계