This would not work well for users who enter the supplier’s reference number for purchase invoices. It is possible, under such a scheme, to have duplicate reference numbers, which would result in invoices from a single supplier being scattered through the list. So it’s better to list suppliers first, as that can be the most distinguishing field for secondary sorting.
That’s why many of us have asked @lubos to have external id field for suppliers’ documents. Both of them, internal progressive number and external ID, should be listed by law in all reports in Italy.
By the way, returning to my request, he can make the naming/sorting settings configurable to match both our needs.
This is already supported. Make reference number on purchase invoices automatic - this would be your internal id. Then create custom field for external id.
The only issue is that custom fields are not exposed on reports. But… this will be solved by new version of custom reports. New custom reports should make it really easy to generate Tax Transaction Report with any columns you require.
So for now, I’ll mark this as an idea until new custom reports are in the program. Then I’ll demonstrate how it would work.