Transactional processing in Messaging Systems

As With any other db/Persistence API , queueing/messaging API must(May
be It should be re-emphasized) support transactional API
and no wonder Oracle AQ supports this.
Set based processing , Enqueueing and Dequeueing array of messages, XML
based payloads
possible with AQ.
While Oracle AQ supports Transactional API in Persistent Queues which it
conveniently leverages the Oracle Database Tables (Queue Tables,IOTs to
be precise)
it was not supporting transactional API in Buffered messages.
EnQueueing and DeQueueing into Persistent Messages have the same
overhead as of doing Select,Insert and/or delete into IOT tables as the
case maybe.
Buffered Messages dont have this overhead with the downside of retention.