（120）View the Exhibits and examine the structures of the PRODUCTS, SALES, and CUSTOMERS tables. You issue the following query:

SELECT p.prod_id, prod_name, prod_list_price, quantity_sold, cust_last_name

FROM products p NATURAL JOIN sales s NATURAL JOIN customers c

WHERE prod_id =148;

Which statement is true regarding the outcome of this query?

A. It executes successfully.

B. It produces an error because the NATURAL join can be used only with two tables.

C. It produces an error because a column used in the NATURAL join cannot have a qualifier.

D. It produces an error because all columns used in the NATURAL join should have a qualifier.

答案：（C）

解析：

虽然没有表结构，但可以猜到

A（X），作为隐式的连接条件的列，不能使用修饰符。因为products和sales在进行连接时需要使用prod_id作为连接条件

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OCP 1Z0-051-120