Structure of the ORDERS table
Structure of the CUSTOMERS table

-Which of the following SQL statements will list the name of each customer stored in the customers table,and,if the customer has placed an order that is contained in the ORDERS table,the order# of any order each customer has placed?
A) SELECT lastname,firstname,order# FROM orders RIGHT OUTER JOIN customers USING (customer#);
B) SELECT lastname,firstname,order# FROM orders LEFT OUTER JOIN customers USING (customer#);
C) SELECT lastname,firstname,order# FROM orders FULL OUTER JOIN customers USING (customer#);
D) both a and c

Question

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Structure of the ORDERS table
  Structure of the CUSTOMERS table
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-Which of the following SQL statements will list the name of each customer stored in the customers table,and,if the customer has placed an order that is contained in the ORDERS table,the order# of any order each customer has placed?​
A) SELECT lastname,firstname,order# FROM orders RIGHT OUTER JOIN customers USING (customer#); 
B) SELECT lastname,firstname,order# FROM orders LEFT OUTER JOIN customers USING (customer#); 
C) SELECT lastname,firstname,order# FROM orders FULL OUTER JOIN customers USING (customer#); 
D) ​both a and c

Quizplus · Accepted Answer

Both RIGHT OUTER JOIN and FULL OUTER JOIN can be used to achieve the desired result. A RIGHT OUTER JOIN will include all records from the right table (customers) and the matched records from the left table (orders), which ensures that all customers are listed even if they haven't placed an order. A FULL OUTER JOIN will include all records when there is a match in either left (orders) or right (customers) table records, which also ensures all customers are listed, including those without orders, and all orders are listed, including those not linked to a customer.

​ Structure of the ORDERS Table

Structure of the ORDERS Table