071考試是OCP認證的一個重要科目,不少考生都在這里受傷,對此我們專門收集整理了近期071考試的原題,并對071題庫進行了講解,希望幫助大家順利通過071考試。
--------------------------------------------
071考試原題分享-第64題、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:該題考的是語法,因為 USING 子句的列部分在 SELECT 列表中不能具有限定符,所以該語句不會執行,把前綴 oi 去掉就可以了,但是其它的列可以用表的別名做為前綴:
SELECT order_id, oi.product_id, order_date
FROM order_items oi JOIN orders o
USING(order_id);
)該題之前有過類似的考題。
-----------------------------------------------
OCP解析公開課時間:【每周五晚8點】
OCP解析公開課地址:https://ke.qq.com/course/326223
OCP解析群資料分享:1015267481 驗證:ocp
另外,除了OCP公開課,OCM題庫直播也同步進行中,OCM最新題庫大爆料-【每周四晚8點】,【微信群直播】,可以聯系咨詢老師進群參與