Some columns are repeated out of multiple tables in a normalized database.
Primary keys are the biggest example. CustomerNumber will be in the
Customer table and the OrderHeader table.

CustomerName may appear in CustomerMaster and OrderHeader to allow for
"one shot" orders. Sometimes it's not worth creating a customer record
for a $1.98 sale. Especially when your accounting department requires a
whole workflow process to create a new customer.


Rob Berendt




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