Mary wants to know when she’s lost a customer. One way to help her would be to produce a report, say in PDF format, showing the top 50 customers from the prior year. Mary could print that report or place it on a private section of her Web site so that she can download it from wherever she happens to be.

Periodically—say, once a week—Mary could request a report that shows the top buyers for that week. That report could also be in PDF format, or it could just be produced onscreen. Mary could compare the two reports to determine who is missing. If she wonders whether a customer such as Tootsie has been ordering, she could request a query report on Tootsie’s activities. Describe the advantages and disadvantages of this solution.