RE: AW: [odb-users] object_already_persistent exception and polymorphic class

[Dieter Govaerts]

Hi Marcel,

> sounds like you catch the exception and then commit the transaction anyway? You
> should not do that. If you do something like
> 
> try
> {
>     odb::transaction t(db.begin());
> 
>     db.persist(new employee("John"));
>     db.persist(new employee("John"));
> 
>     t.commit();
> }
> catch (const odb::exception& e)
> {
>     std::cerr << e.what () << endl;
> }
> 
> then the transaction is rolled-back automatically because ODB's transaction class
> conforms to the RAII principle.
> This should solve your problem.

Yes, you are right. What else do we need transactions for? I must have been asleep :-/.

The problem was that I can not rollback the transaction. The operation is part of a greater whole which I do not have control over. I knew sqlite didn't support nested transactions but it runs out it has savepoints which can serve the same purpose.

Problem solved. Thank you.

Dieter