RE: makeTransactional

Question

David --
This is an excellent question. I believe that Kodo's behavior is
correct; i.e. that calling makeTransactional() on a persistent
non-transactional instance during an optimistic transaction does not
guarantee that the state of the instance is compared to that of the data
store. However, my evidence for this is a little shaky:
Section 5.8 of the JDO specification covers optimistic transactions.
Check out p. 40 and 41 where the makeTransactional() method is
discussed. Only for persistent dirty instances does the spec say the
state of the instance is verified against the data store during commit.
The spec also mentions that users should call refresh() if they want to
make sure the state of the instance in memory is correct (though
refresh() is an expensive operation).
From the above evidence I believe that p-clean instances are nevercompared to the datastore for consistency. But as I noted, this isn't a
whole lot to go on, so I could be wrong. I encourage you to contact the
JDO spec team about the issue... or if you don't we on the Kodo team
will get around to it eventually.
Let us know if you get any clarification!
-- Abe White
-----Original Message-----
From: David Ezzio
To: Tech Trader JDO List
Sent: 8/12/01 4:59 PM
Subject: makeTransactional
Concerning the makeTransactional() method, the spec (V 0.95 p 79) says,
"These methods are also used to mark a nontransactional persistent
instance as being part of the read-consistency set of the transaction."
For transactions with optimistic on and nontransactional read on, I took
this statement to imply that a call to makeTransactional would force a
comparison of the age of the object's concurrency field (its optimistic
lock) to the value in the datastore at the time of transaction commit.
I believed that this would occur even if there were nothing dirty to
write in the object or, even, in the transaction. If there were an age
descrepancy with any of the transactional objects, I expected that an
exception would be raised rather than having the transaction commit.
However, I am not seeing the behavior that I expected in Kudo. So my
question is: am I confused or is there a bug?
David

Answer 1

Craig et al.,
We either have confusion on my part, lack of clarity in the spec, or a
bug in Kudo. Can you perform some triage?
Thanks,
David