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  • OCP-1Z0-051-V9.02-123题

    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:
    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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  • 原文地址:https://www.cnblogs.com/hzcya1995/p/13316867.html
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