RE: [ojb-users] ODMG Cascading Updates : possible/probable bug.

[Charles A. <cha...@hp...>]

Hi Again,

Has anyone been able to have a quick look at this yet ? Either we're making
an obvious and silly mistake, or there is a fundamental error in the ODMG
transaction code, which could have big consequences.

Thanks,

Charles.

> -----Original Message-----
> From: Charles Anthony [mailto:cha...@hp...]
> Sent: 08 April 2002 13:18
> To: 'obj...@li...'
> Cc: 'tho...@it...'
> Subject: [ojb-users] ODMG Cascading Updates : possible/probable bug.
> 
> 
> Hello All,
> 
> In OJB-0.8.375, cascading updates appears to be broken when 
> using ODMG.
> 
> A colleague and I have managed to abstract the problem into a 
> simple test
> case.
> test.ClassA has a collection of test.ClassB
> test.ClassB has a reference back to test.ClassA
> i.e. a simple bi-directional 0..n relationship between ClassA 
> and ClassB.
> 
> We create an instance of ClassA, and add an instance of ClassB to the
> classBs Collection; we then lock the instance of ClassA for write, and
> commit the transaction.
> 
> Extract :
> ClassA a1 = new ClassA("A 1");
> ClassB b1 = new ClassB("B 1");
> a1.getClassBs().add(b1);
> 
> Transaction tx = null;
> tx = odmg.newTransaction();
> tx.begin();
> tx.lock(a1, tx.WRITE);
> tx.commit();
> 
> When the transaction is committed, the ClassA row is 
> correctly inserted into
> the database, and ClassB row is also inserted into the database.
> Unfortunately, it is inserted twice, resulting in a Primary 
> key violation
> (I've remove the primary key constraint in the attatched SQL).
> 
> It is some time since I've been able to spend anytime on OJB, 
> and so my
> knowledge of its internals has faded somewhat. However, by 
> stepping through
> in debug, it seems that the the ClassB instance is committed 
> twice, once in
> the collection and once on it's own.
> 
> I attach the test case, the repository_user.xml and the SQL 
> to create the
> tables. We're using SQL Server, but I'm fairly sure this is a platform
> independent problem.
> 
> Are we doing something wrong, or is this a bug ?
> 
> Thanks,
> 
> Charles.
> 
> 
> 
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This email and any attachments are strictly confidential and are intended
solely for the addressee. If you are not the intended recipient you must
not disclose, forward, copy or take any action in reliance on this message
or its attachments. If you have received this email in error please notify
the sender as soon as possible and delete it from your computer systems.
Any views or opinions presented are solely those of the author and do not
necessarily reflect those of HPD Software Limited or its affiliates.

 At present the integrity of email across the internet cannot be guaranteed
and messages sent via this medium are potentially at risk.  All liability
is excluded to the extent permitted by law for any claims arising as a re-
sult of the use of this medium to transmit information by or to 
HPD Software Limited or its affiliates.