Makes sense. But customer order numbes, cust ids and those other fields should be generated through some sort of script. I would not expect a customer to enter something like that. If you look at large websites, no site has cust id 1, or cust id 99. Hence they have some sort of script generating a unique number, and inserting it as a unique key in the cust id table.
Iluxa, it's not about whether your not YOU know the relationship, it's about the next maintenance programmer thats going to come after you. Also, C10001 would work pefectly fine in a schema, so I don't see a problem there.
Great discussion guys/girls. Sorry for the original poster, I sort of hijacked this uknowingly.
I just think that there's a better way to design a table than a auto-number/next sequence. It might be fine initially, but perhaps it would complicate maintenance down the line. I mean, if you can reference real data, why create an extra field that is somewhat meaningless? Perhaps different rules apply to the business world?