AW: [Objectbridge-developers] Order of commit in ODMG transaction

[Mahler T. <tho...@it...>]

Hi again Charles,

> -----Urspr=FCngliche Nachricht-----
> Von: Charles Anthony [mailto:cha...@hp...]
> Gesendet: Dienstag, 25. September 2001 11:47
> An: 'obj...@li...'
> Betreff: [Objectbridge-developers] Order of commit in ODMG =
transaction
>=20
>=20
> Hello,
>=20
> I have objects AccountingTransaction and AccountingEntry.=20
> There is a one to
> many relationship between the Transaction and Entry. This is=20
> backed up by a
> foreign-key constraint in the database.
>=20

Ooops: Proper handling of fk-constraints is definetly not supported yet =
:-(


> I want to be able to commit the Transactions and Entries=20
> within the same
> (ODMG) transaction (so that either all or none are created in=20
> the database).
>=20
> Unfortunately, it seems that sometimes the AccountEntry gets=20
> created before
> the AccountTransaction within the database transaction of the=20
> commit, thus
> violating the foreign key constraint.
>=20
> After a quick look at the sourcecode, it seems that the=20
> ObjectStateTable
> stores the ObjectTransactionWrapper's in a hashtable, and=20
> that on Commit,
> the ObjectTransactionWrapper's are processed in hashtable order.
>=20
> Whilst I'm not sure this classifies as a bug, it would be an=20
> immense benefit
> to have the objects committed in order; it shouldn't be too=20
> difficult to
> store the objects order in a Vector (or similar) on the=20
> ObjectStateTable,
> and process the Vector on commit.
>=20

I (as a lazy programmer) won't classify it as a bug: it's merely a =
feature
that is not yet implemented yet. We will need a depency graph to =
determine
the right processing order. It should be not too difficult to generate =
such
a graph from the metadata. I'll put it on my my todo list!


> I am sure I'm missing something pretty obvious here; I'm not=20
> sure what it is
> though.
>=20
> Is there any chance of a solution to this problem ?
>=20

The only thing that will help you right now is to drop the foreign key
constraints in the RDBMS.
If you are forced to use fk constraints please tell me: I'll put this
feature to the top of my todo list! But it will take at least 1 week as =
I
want to get out the next release this week.

--Thomas

> With many thanks,
>=20
> Charles.
>=20
>=20
> This email and any attachments are strictly confidential and=20
> are intended
> solely for the addressee. If you are not the intended=20
> recipient you must
> not disclose, forward, copy or take any action in reliance on=20
> this message
> or its attachments. If you have received this email in error=20
> please notify
> the sender as soon as possible and delete it from your=20
> computer systems.
> Any views or opinions presented are solely those of the=20
> author and do not
> necessarily reflect those of HPD Software Limited or its affiliates.
>=20
>  At present the integrity of email across the internet cannot=20
> be guaranteed
> and messages sent via this medium are potentially at risk. =20
> All liability
> is excluded to the extent permitted by law for any claims=20
> arising as a re-
> sult of the use of this medium to transmit information by or to=20
> HPD Software Limited or its affiliates.
>=20
>=20
>=20
> _______________________________________________
> Objectbridge-developers mailing list
> Obj...@li...
> https://lists.sourceforge.net/lists/listinfo/objectbridge-developers
>=20