Re: DB dead lock issue with deletePersistent calls

Bruno CROS wrote:
> No. I don't known how to write such a test. But i have an idea where it
> occurs in the persistent graph.
> 
> I use locks on OJB master object (at start of transaction) when possible
> (even with delete). I think with this, two transactions can't run at the
> same time on the same part of persistent graph. 

Only if implicit locking is enabled, else only the specified object is 
locked and not the whole graph. If not enabled you have to lock all 
objects before changing or deleting by yourself.
You can enable implicit locking on a per tx manner using OJB's 
odmg-extensions - TxExt.
http://db.apache.org/ojb/docu/guides/odmg-guide.html#The+TransactionExt+Interface
In this case all referenced objects will implicit locked with the same 
lock mode as the master object (on very large object graphs this could 
slow down performance).

regards,
Armin