OCP考试题库以前是比较稳定的，但在2018年随着oracle的调整，不断的有新题出现，增加考试的难度，对此，我们专门收集整理了071的考试真题，分享给大家。
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071题库分享-第64题、choose the best answer:
View the Exhibit and examine the structure of the ORDERS and ORDER_ITEMS tables.
Evaluate the following SQL statement:
SELECT oi.order_id, product_id, order_date
FROM order_items oi JOIN orders o
USING(order_id);
Which statement is true regarding the execution of this SQL statement?
A) The statement would not execute because the table alias prefix is not used in the USING clause.
B) The statement would not execute because the column part of the USING clause cannot have a qualifier in the SELECT list.
C) The statement would not execute because table aliases are not allowed in the JOIN clause.
D) The statement would not execute because all the columns in the SELECT clause are not prefixed with table aliases.
Anser：B
(解析：该题考的是语法，因为 USING 子句的列部分在 SELECT 列表中不能具有限定符，所以该语句不会执行，把前缀 oi 去掉就可以了，但是其它的列可以用表的别名做为前缀：
SELECT order_id, oi.product_id, order_date
FROM order_items oi JOIN orders o
USING(order_id);
)该题之前有过类似的考题。
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