--- In ib-support@y..., "luisfelipepetrycabral" <lcabral@a...> wrote:

> What I don't really understand is that App-A updates the
> MASTER_DUMMY field, not the MASTER_KEY that is referenced by the
> foreign key of DETAIL table.

Luis, it is as IB/FB designed. Locks are watched on "record" level,
not "column". So, second transaction see that master record was
changed and, don't knowing (because first transaction is'nt commited
yet) about does changes affected referenced columns or not,
pessimistically raises lock conflict.

Best regards, Alexander V.Nevsky.