permalink use record 'num' field
I have a problem, I need to use the record Number 'num' field in the permalink, but it will not allow me to do this.
$GLOBALS['PERMALINKS']['autopopulate_fromFields'] = array('num', 'name', 'title'); // the first field in this list with content will be used to create the permalinks. To use multiple fields separate them with spaces
This is a problem for me as using this field to denote the invoice number, and generating a permalink, this will ensure that the invoice numbers will remain intact and as direct links on the system. I can not use another field as they would not auto-increment, and I do not want them to be manually entered.
I can't find a solution to this.
any suggestions greatly recieved.
Basically just need the number field to be used as the permalink so that an invoice uses the number as the permalink which is generated on saving the record, using prefix op- to denote online purchase.
so the link would be http://address.com/op-123/
op- is the default on the permalink field.
when I go to save it says 'you must enter a value for permalink!