![[SQL문제풀기] 월별 잡은 물고기 수 구하기](https://image.inblog.dev?url=https%3A%2F%2Fsource.inblog.dev%2Ffeatured_image%2F2025-01-16T15%3A10%3A53.470Z-c7b20d48-7089-4da3-b444-2bcbc7fd464d&w=3840&q=75)
Contents
문제문제
내가 작성한 정답 1
SELECT COUNT(ID) FISH_COUNT , MONTH(TIME) MONTH
FROM FISH_INFO
GROUP BY 2
ORDER BY 2 ASC내가 작성한 오답
: MySQL의 ONLY_FULL_GROUP_BY SQL 모드에서는 GROUP BY 절에 포함되지 않은 비집계 열을 SELECT 또는 ORDER BY 절에서 사용할 수 없다.
내가 작성한 정답 2
SELECT COUNT(ID) FISH_COUNT , CAST(DATE_FORMAT(TIME,'%m') AS UNSIGNED) MONTH
FROM FISH_INFO
GROUP BY 2
ORDER BY 2 ASCSELECT COUNT(ID) FISH_COUNT , CONVERT(DATE_FORMAT(TIME,'%m'),UNSIGNED) MONTH
FROM FISH_INFO
GROUP BY 2
ORDER BY 2 ASC형변환 함수들 CAST , CONVERT
CAST(COLUMN AS UNSIGNED) : 컬럼을 숫자로 변환
CAST ( COLUMN AS data_type [ ( length ) ] )
CONVERT ( COLUMN, data_type [ ( length ) ] )
Share article