Subject Re: [firebird-support] New TPB constant usage
Author Ann W. Harrison
slalom91 wrote:
> Hi,
> Can someone provide me the ideal transaction parameters for my
> purposes. I have a multi-threaded, multi-user application which
> amounts to an order entry system.

Different people will have different answers and different
answers are appropriate in different circumstances.

I would argue for isc_tpb_concurrency and take the defaults
on everything else. That gives each transaction a consistent
view of data.

When one transaction attempts to update or delete a record
that was inserted, updated, or deleted by a concurrent
transaction, it will wait until the second transaction completes.
That behavior avoids a problem called live-lock where two
transactions attempt to update the same records, both fail,
both retry, both fail, and the process continues forever at
great expense.

If there is relatively low contention but transactions
are long - requiring user input while open for example - you
might use isc_tpb_nowait to get an instant error on update