[ORACLE_SQL]오프라인/온라인 판매 데이터 통합하기(ㅇ)

https://school.programmers.co.kr/learn/courses/30/lessons/131537

-- 코드를 입력하세요
SELECT TO_CHAR(SALES_DATE,'YYYY-MM-DD') AS SALES_DATE, PRODUCT_ID, USER_ID, SALES_AMOUNT FROM ONLINE_SALE 
WHERE EXTRACT(YEAR FROM SALES_DATE) = '2022' AND EXTRACT(MONTH FROM SALES_DATE) = '03'
UNION ALL
SELECT TO_CHAR(SALES_DATE,'YYYY-MM-DD') AS SALES_DATE, PRODUCT_ID, NULL USER_ID, SALES_AMOUNT FROM OFFLINE_SALE
WHERE EXTRACT(YEAR FROM SALES_DATE) = '2022' AND EXTRACT(MONTH FROM SALES_DATE) = '03'
ORDER BY SALES_DATE ASC, PRODUCT_ID ASC, USER_ID ASC