Q199
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
找个类似的表，按题目做个类似的输入
提示max 在这里不可用。。
把子查询语句单独拿出运行。
A 和B 选项不符合题目要求。。A选项答案无返回值。B返回值不符合题目意思。
C选项 返回只有一个值。。
D为正确选项
参考结果如下图