다음은 PRODUCTS와 SALES_HISTORY의 전체 데이터이다. SQL 실행 후 PRODUCT_ID가 101, 102, 103인 상품의 DISCOUNT_RATE를 순서대로 나열한 것은?
보기
PRODUCTS
| PRODUCT_ID | DISCOUNT_RATE |
|---|---|
| 101 | 4 |
| 102 | 8 |
| 103 | 12 |
SALES_HISTORY
| PRODUCT_ID | SALE_DATE | DISCOUNT |
|---|---|---|
| 101 | 2026-04-03 | 10 |
| 101 | 2026-04-10 | 30 |
| 102 | 2026-03-25 | 40 |
UPDATE PRODUCTS T
SET DISCOUNT_RATE = (SELECT AVG(NULL)
FROM SALES_HISTORY H
WHERE H.PRODUCT_ID = T.PRODUCT_ID
AND H.SALE_DATE >= DATE '2026-04-01');- 1NULL, 8, 12
- 220, NULL, NULL
- 30, 0, 0
- 4NULL, NULL, NULL
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