（154）View the Exhibit and evaluate structures of the SALES, PRODUCTS, and COSTS tables. Evaluate the following SQL statement:

SELECT prod_id FROM products

INTERSECT

SELECT prod_id FROM sales

MINUS

SELECT prod_id FROM costs;

Which statement is true regarding the above compound query?

A. It produces an error.

B. It shows products that were sold and have a cost recorded.

C. It shows products that were sold but have no cost recorded.

D. It shows products that have a cost recorded irrespective of sales.

答案：（C）

解析：

三个集合操作符的优先级相同。

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OCP 1Z0 051 154