I have worked on a system that took exaclty this approach for ~17 years. The database was Oracle, at the time we started 'SKIP LOCKED' was not even a documented feature of the Oracle DBMS. It is now. The approach worked quite well for us and happily working today at several large banks. Also, Oracle sells what I think they call AMQ (Advanced Message Queing) that provides a messaging API but uses the DBMS for storage. No idea how it performs relative to dedicated persistent messaging solutions, but I would guess that it probably good enough for many workloads.