Review the Northwind database for the table structure to do this. You shouod have a customer table, a service table, and then a Service Details junction table.
You basicaly want to keep information on customers, items, and service incidents. This is in Northwind.
Also, you shouldn't have to do what you are proposing in the second paragraph of your post if you are using the proper junction tables. This will allow you to not only show all of the service incidents per customer, but per part as well.
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