Is it possible for me to have a non-numeric revision number? We intend to use a application generated GUID (which will be alphanumeric) as sequences lead to problems during data migration. The documentation says it has to be an integer or long property.
no, that's not possible, as Envers relies on the fact that the revisions form a strictly increasing sequence of numbers (when searching for an entity at revision N, you have to look for the latest modification at of before revision N. So to be able to express "at or before", you need some kind of order on the revision identifiers. Numbers are a very good candidate :) )