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WITH RECURSIVE cte_name AS ( initial_query -- anchor member UNION ALL recursive_query -- recursive member that references to the CTE name)SELECT * FROM cte_name; 재귀 쿼리의 기본적인 구조는 이렇게 생겼다.초기 쿼리를 anchor member, 재귀 쿼리 부분을 recursive member재귀 쿼리문은 anchor member와 recursive member를 UNION ALL 이나 UNION DISTINCT 사용해 결합한다. WITH RECURSIVE cte_count (n) AS ( SELECT 1 -- 초기값 UNION ALL ..

처음 내 풀이-- 시간대별 입양 건수 SELECT HOUR(datetime) AS hour, COALESCE(COUNT(animal_id), 0) AS countFROM animal_outs GROUP BY 1ORDER BY 1 -- 시간대별 입양 건수 -- 재귀쿼리 WITH RECURSIVE hours AS ( SELECT 0 AS hour UNION ALL SELECT hour + 1 FROM hours WHERE hour  재귀쿼리 : https://hyezdata.tistory.com/108