15、 請問下列指令何者可得到”所提供的產品之平均產品進貨價格高於 1000 的廠商代碼
(V_NUM)”? 請根據下面的資料表作答(假設一位廠商可提供多項產品,一項產品只能由
一位廠商提供)。 (A) SELECT V_NUM, AVG(P_PRICE) >1000
FROM PRODUCT;
(B) SELECT V_NUM
FROM PRODUCT
GROUP BY V_NUM;
WHERE AVG(P_PRICE) >1000;
(C) SELECT V_NUM
FROM PRODUCT
GROUP BY V_NUM;
HAVING AVG(P_PRICE) >1000
(D) SELECT V_NAME
FROM PRODUCT
HERE P_PRICE = (SELECT AVG(P_PRICE) >1000 FROM PRODUCT);