알고리즘 풀이/프로그래머스
프로그래머스 - ORACLE SQL (GROUP BY)
배게
2019. 12. 7. 16:14
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고양이와 개는 몇마리 있을까
SELECT animal_type, count(*)
FROM animal_ins
GROUP BY animal_type
ORDER BY animal_type
동명 동물 수 찾기
SELECT name,count
FROM
(SELECT name, count(name) count
FROM animal_ins
WHERE name is not NULL
GROUP BY name
ORDER BY name)
WHERE count >=2
==================
SELECT name, count(*)
FROM animal_ins
WHERE name is not NULL
GROUP BY name
HAVING count(*)>=2
ORDER BY name
입양 시각 구하기(1)
SELECT HOUR, count(HOUR)
FROM
(SELECT to_char(datetime,'HH24') HOUR
FROM animal_outs)
WHERE HOUR >=9 and HOUR<=19
GROUP BY HOUR
ORDER BY HOUR
입양 시각 구하기(2) PASS