새로운 문법을 검색해 가면서 풀었던 문제.
문제가 길지 않아서 쉽게 풀 거라고 생각했는데, 아니었다...
WITH RECURSIVE numbers AS (
SELECT 2 AS num
UNION ALL
SELECT num + 1 FROM numbers WHERE num < 1000
),
primes AS (
SELECT num
FROM numbers n
WHERE NOT EXISTS (
SELECT 1 FROM numbers d
WHERE d.num < n.num AND d.num > 1 AND n.num % d.num = 0
)
)
SELECT GROUP_CONCAT(num SEPARATOR '&') AS prime_list
FROM primes;