[Database]: How to get the custom fields for products in an Order?

[EvanGR]

Database related question, didn't know which subforum to ask...

I am building a custom SQL query, and I want to get the selected custom fields for each product in a given Order.
I mostly care about the strings (labels) so I can print a report.
e.g.
T-shirt Red XL

Can you help me find the DB structure for that info, and perhaps some pseudocode for the logic?

Thank you