Which database fields show multiple orders by the same customer

[dowser]

I'm merging two different databases - one is from mcart (actually MerchantPal) and has data for almost 8 years and I want to merge it into osc database. How does OSC handle multiple orders from the same customer? Which field(s) change to show that? I need to determine which fileds from the old database should get imported into OSC.

 

I have quite a few repeated orders from the same customer, that's why it's important to do it right.

 

Any input would be appreciated.

[♥ecartz]

The osCommerce database schema identifies a particular order as belonging to a particular customer by the customers_id field in the orders table. You can have an arbitrary number of orders belonging to the same customers_id.