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Chapter 5 Database Processing
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jobs, and relationships must accurately reflect your view of the business. If the data model is wrong, the
database will be designed incorrectly, and the applications will be difficult to use, if not worthless.
Do not proceed unless the data model is accurate.
As a corollary, when asked to review a data model, take that review seriously. Devote the
time necessary to perform a thorough review. Any mistakes you miss will come back to haunt
you, and by then the cost of correction may be very high with regard to both time and expense.
This brief introduction to data modeling shows why databases can be more difficult to develop
than spreadsheets.