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)
阅读(759) | 评论(0) | 转发(0) |
