SQL Connection - EJB Transaction Integration

Question

I am currently running Kodo 2.3.2 and JBoss 3.0 and I'm having the following
problem:
The SQLConnection returned from the PersistenceManager isn't always
transactionally consistent when run within EJBs (BMT or CMT).
For example, I have BeanA (BMT) that starts a transaction then retrieves a
PM->SQL connection then performs an update using direct SQL (non-JDO). Then
BeanA calls BeanB (CMT) that retrieves a PM and performs a JDO update. Once
BeanB completes, BeanA rolls back the entire transaction. The problem is
that the (non-JDO) SQL connection update isn't rolled back.
I only see this behavior the very first time I run the scenario. If I run
the scenario 2 -> N times it will be transactionally consistent.
Does anyone have any ideas what is going wrong the first time I run this
scenario?
I have multiple scenarios with BMT/CMT beans using JDO and non-JDO updates
where the first iteration of the update cause the non-JDO updates to not
roll back.
Thanks in advance.

Answer 1

Are you using optimistic transactions? If you're using optimistic
transactions with JDO, then an actual database transaction isn't started
until you call commit(). At that time Kodo starts a transaction, flushes
all the changes that have been made, and ends the transaction all at once.
That's why optimistic transactions are so nice -- they don't consume any DB
resources during the length of the transaction.
Of course, that also means that any connection you retrieve won't be
transactionally consistent, cause there's no transaction!