SELECT 01

과일로 만든 아이스크림 고르기

SELECT F.FLAVOR
FROM FIRST_HALF F INNER JOIN ICECREAM_INFO I
ON F.FLAVOR = I.FLAVOR
WHERE TOTAL_ORDER > 3000 AND INGREDIENT_TYPE IN ('fruit_based');

재구매가 일어난 상품과 회원 리스트 구하기

SELECT USER_ID,PRODUCT_ID
FROM ONLINE_SALE
GROUP BY USER_ID,PRODUCT_ID
HAVING COUNT(*) >=2
ORDER BY USER_ID ASC , PRODUCT_ID DESC;

동물의 아이디와 이름

SELECT ANIMAL_ID, NAME
from ANIMAL_INS 
order by ANIMAL_ID;

여러 기준으로 정렬하기

SELECT ANIMAL_ID,NAME,DATETIME
FROM ANIMAL_INS
ORDER BY NAME,DATETIME DESC;

상위 n개 레코드

SELECT NAME 
FROM ANIMAL_INS
WHERE DATETIME IN (SELECT MIN(DATETIME) FROM ANIMAL_INS);

조건에 맞는 회원수 구하기

SELECT COUNT(*)
FROM USER_INFO
WHERE JOINED BETWEEN '2021-01-01' AND '2021-12-31'AND AGE BETWEEN 20 AND 29;

ORACLE : TO_CHAR

SELECT COUNT(*)
FROM USER_INFO
WHERE TO_CHAR(JOINED,'YYYY-MM-DD') between '2021-01-01' and '2021-12-31' and AGE BETWEEN 20 AND 29;