OCP-1Z0-051-V9 02-123题

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123. View the Exhibits  and examine the structures of the PRODUCTS, SALES,  and CUSTOMERS

tables.

You need to generate a report that gives details of the customer's last name, name of the product,  and

the quantity sold for all customers in ' Tokyo' .

Which two queries give the required result? (Choose two.)

A. SELECT c.cust_last_name,p.prod_name, s.quantity_sold

FROM sales s JOIN products p

USING(prod_id)

JOIN customers c

USING(cust_id)

WHERE c.cust_city='Tokyo';

B. SELECT c.cust_last_name, p.prod_name, s.quantity_sold

FROM products p JOIN sales s JOIN customers c  

ON(p.prod_id=s.prod_id)

ON(s.cust_id=c.cust_id)

WHERE c.cust_city='Tokyo';

C. SELECT c.cust_last_name, p.prod_name, s.quantity_sold

FROM products p JOIN sales s

ON(p.prod_id=s.prod_id)

JOIN customers c

ON(s.cust_id=c.cust_id)

AND c.cust_city='Tokyo';

D. SELECT c.cust_id,c.cust_last_name,p.prod_id, p.prod_name, s.quantity_sold 

FROM products p JOIN sales s

USING(prod_id)

JOIN customers c

USING(cust_id)

WHERE c.cust_city='Tokyo';

Answer: AC

答案解析：

参考：http://blog.youkuaiyun.com/rlhua/article/details/12877591

B语法错误

D中p.prod_id不应该跟限定的表别名。

不要对USING子句中使用的列加以限定。

USING子句中引用的那些列不能在SQL 语句的任何位置使用限定词（表名或别名）。

如果在SQL 语句的另一个位置使用了同一列，则不要对其设置别名。

           

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