I am using the product registration functionality, and want to use custom fields to retrieve pertinent information from the users tax invoice. But as my SQL skill is non-existent, I was wondering if someone could assist.
 
Can anyone draft an SQL statement (which I will put in the custom field details) to do the following:
 
Retrieve from table va_orders_items
the following field order_id
for currently logged in user.
 
Is this possible, especially the part about retrieving information for logged in user?