ubuntu 12, openjdk7
we have encountered problems with the jdbc message store, when polling concurrently from two different queues.
The sql statement looks like this:
SELECT min(MESSAGE_ID) from MESSAGE where CREATED_DATE = (
SELECT min(CREATED_DATE) from MESSAGE, GROUP_TO_MESSAGE
where MESSAGE.MESSAGE_ID = GROUP_TO_MESSAGE.MESSAGE_ID
and GROUP_TO_MESSAGE.GROUP_KEY = ? and MESSAGE.REGION = ?
and does something like: look for message ids that where created at a date that the youngest message
in the requested queue was create. if more than one id, take the min. The intention is fifo behaviour.
BUT: if two messages were created at the same time (e.g. by a splitter) and routed to different queues, there
is a good chance that a poller polling on queue1 fetches a messages from queue2, because the messages
where created at the same time.
The "outer" where clause is missing the joining "GROUP_KEY = ?" condition.
I think this is a bug. Even more it behaves non deterministic and depends on various timing conditions.
The provided demo shows the error. description see forum thread ..