You want to extend the schema shown in Table 4-16 to include information about customer payments. Some

Question:

You want to extend the schema shown in Table 4-16 to include information about customer payments. Some customers make installment payments on each invoice. Others write a check to pay for several different invoices.
a. Modify the set of tables in Table 4-16 to store this additional data.
b. Identify the primary key for each new table you create.