Question

What would be the primary key in a relational table for VALID_INVOICES?

1) Vendor name
2) Invoice number
3) Vendor number
4) Invoice date

Answer 1

The primary key for VALID_INVOICES would be the Invoice number, as it is unique to each invoice and allows for easy identification of each record.

Step-by-step explanation:

The primary key in a relational table for VALID_INVOICES would be the Invoice number. The invoice number is unique to each invoice, which ensures that each record in the table can be uniquely identified. Vendor name and Vendor number might not be unique for every invoice as a single vendor can have multiple invoices, while the Invoice date is not unique because multiple invoices can be issued on the same date.