Case Study in Variation: An International E-Tail System
Suppose an e-tail system must process sales orders in several different nations. Initially I have to handle just the United States and Canada. I look at my requirements and see several things that vary. I note these in Table 20-1.
Table 20-1. Different Cases Depending Upon Residence of Customer
Calculate freight based on UPS charges.
Use U.S. postal rules for verifying addresses.
Calculate tax based on sales and/or services depending upon locale.
Handle money in U.S. $.
Calculate freight based on main Canadian shipper.
Use Canadian postal rules for verifying addresses.
Calculate tax based on sales and/or services depending upon Canadian province taxing rules (using ...
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