Hello everyone
I have a shop that sell trackday events, and in this, a customer should be able to choose a “Drivernumber” for the event.
It must be possible to select numbers from 1-999, and the same number may only be used once!
It would be preferable for it to be selected as an attribute to the product (the event), because it will then be exported to the same line as the product itself in the csv report, when I make csv order export (It is used for the timekeepers on the event).
I have tried me make a stockable custom field, but I cannot be allowed to make more than 192 options / numbers before the page crashes - probably because it is too heavy for the database. I felt that the page-performance where suffering badly when I create the 192 child products, so I can imagine that 999 would be much worse.
Aside from that the site crashes and the performance is poor, then the solution with stockable custom fields is fine because I easily can steer that only one of each number is sold.
I then thought of a solution where a customer writes a desired number in a text field. Preferable on the product itself as an attribute, but a mandatory field in the customer profile could also be used. The problem here is that the same number may not be selected twice, and there must therefore be made some kind of validation on the field, so that the max input is 3 numbers, and the same combination cannot be written twice. ie field content at must be unique.
Any thoughts on how to achieve this, is much appreciated

System specs:
Joomla 2.5
Virtuemart 2.0.16