SQLD 기출문제 예상문제 388번

다음 문제를 풀어보세요.

다음 중 주어진 'SALES' 테이블과 PIVOT 절을 사용한 SQL 쿼리의 실행 결과를 고르시오.

[테이블 구조: SALES]

CREATE TABLE SALES (
    PRODUCT_CATEGORY VARCHAR2(50),
    SALES_MONTH VARCHAR2(3),
    SALES_AMOUNT NUMBER
);

[테이블 데이터: SALES]

INSERT INTO SALES VALUES ('Electronics', 'Jan', 100);
INSERT INTO SALES VALUES ('Electronics', 'Feb', 150);
INSERT INTO SALES VALUES ('Electronics', 'Mar', 180);
INSERT INTO SALES VALUES ('Clothing', 'Jan', 80);
INSERT INTO SALES VALUES ('Clothing', 'Feb', 120);
INSERT INTO SALES VALUES ('Clothing', 'Mar', 100);
INSERT INTO SALES VALUES ('Books', 'Jan', 50);
INSERT INTO SALES VALUES ('Books', 'Mar', 200);

[SQL 쿼리]

SELECT *
FROM (
    SELECT
        PRODUCT_CATEGORY,
        SALES_MONTH,
        SALES_AMOUNT
    FROM SALES
)
PIVOT (
    SUM(SALES_AMOUNT)
    FOR SALES_MONTH IN ('Jan' AS Jan_Sales, 'Feb' AS Feb_Sales, 'Mar' AS Mar_Sales)
)
ORDER BY PRODUCT_CATEGORY;