33.choose the best answer

View the Exhibit and examine the structure of the ORDER_ITEMS table.

Examine the following SQL statement:

SELECT order_id, product_id, unit_price

FROM order_items

WHERE unit_price =

(SELECT MAX(unit_price)

FROM order items

GROUP BY order_id);

You want to display the PRODUCT_ID of the product that has the highest UNIT_PRICE per ORDER_ID.

What correction should be made in the above SQL statement to achieve this?

A) Replace = with the >ALL operator.

B) Replace = with the >ANY operator.

C) Remove the GROUP BY clause from the subquery and place it in the main query.

D) Replace = with the IN operator.

Answer：D

(解析：题意是希望显示每个 ORDER_ID 具有最高 UNIT_PRICE 的产品的 PROT_ID 的信息)