Contents of the CUSTOMERS table

-Based on the contents of the CUSTOMERS table,which SQL statement will display the customers residing in the same state as customer#1013?
A) SELECT customer# FROM customers WHERE customer# = (SELECT state FROM customers WHERE state = 'NJ');
B) SELECT customer# FROM customers WHERE state = (SELECT state FROM customers WHERE customer#=1013);
C) SELECT customer# FROM customers WHERE customer# IN (SELECT state FROM customers WHERE state = 'NJ');
D) SELECT customer# FROM customers WHERE state EXISTS (SELECT state FROM customers WHERE customer#=1013);

Question

Contents of the CUSTOMERS table​
 
-​Based on the contents of the CUSTOMERS table,which SQL statement will display the customers residing in the same state as customer#1013?
A) ​SELECT customer# FROM customers WHERE customer# = (SELECT state FROM customers WHERE state = 'NJ'); 
B) ​SELECT customer# FROM customers WHERE state = (SELECT state FROM customers WHERE customer#=1013); 
C) ​SELECT customer# FROM customers WHERE customer# IN (SELECT state FROM customers WHERE state = 'NJ'); 
D) ​SELECT customer# FROM customers WHERE state EXISTS (SELECT state FROM customers WHERE customer#=1013);

Quizplus · Accepted Answer

We want to display customers residing in the same state as customer#1013. To find the state of customer#1013, we use subquery (SELECT state FROM customers WHERE customer#=1013) in the WHERE clause. Then we select customer# from the customers table where the state matches the state of customer#1013. The correct syntax for this is option B: SELECT customer# FROM customers WHERE state = (SELECT state FROM customers WHERE customer#=1013);

Contents of the CUSTOMERS Table​

Contents of the CUSTOMERS Table