Examine the description of the CUSTOMERS table:
CUSTNO is the PRIMARY KEY.
You must determine if any customers’ details have been entered more than once using a different CUSTNO, by listing all duplicate names.
Which two methods can you use to get the required result? (Choose two.)
To determine if any customers' details have been entered more than once using a different CUSTNO, you can use a self join and a subquery. A self join is useful because it allows you to join the table with itself on the CUSTNAME field and check for different CUSTNO values, effectively identifying duplicates. A subquery can also achieve this by selecting CUSTNAMEs that appear more than once in the table. These two methods are effective for identifying duplicate entries based on names while cross-referencing different CUSTNOs.
Answer A,E