SUM, MIN, MAX

https://programmers.co.kr/learn/courses/30/parts/17043

최댓값 구하기

SELECT DATETIME
FROM ANIMAL_INS
ORDER BY DATETIME DESC
LIMIT 1

최솟값 구하기

SELECT DATETIME
FROM ANIMAL_INS
ORDER BY DATETIME
LIMIT 1

동물 수 구하기

SELECT COUNT (*)
FROM ANIMAL_INS

중복 제거하기

SELECT COUNT (DISTINCT NAME) AS count
FROM ANIMAL_INS
WHERE NAME != 'NULL'