SELECT COUNT(ID) AS FISH_COUNT, MONTH(TIME) AS MONTH
FROM FISH_INFO
GROUP BY MONTH
ORDER BY MONTH
간단하게 Month 사용하면 애초에 숫자형식으로 나옴
하지만 DATE_FORMAT을 이용한 방법은 없을까 고민한 결과 CAST와 CONVERT를 찾았다
-- 문자를 숫자로 바꾸는 방법 CAST, CONVERT
-- CONVERT('123', UNSIGNED) = CAST('123' AS UNSIGNED)
-- CAST('3.14' AS FLOAT) - 소수점
SELECT COUNT(ID) AS FISH_COUNT, CAST(DATE_FORMAT(TIME, "%c") AS UNSIGNED) AS MONTH
FROM FISH_INFO
GROUP BY MONTH
ORDER BY MONTH