Subject [firebird-support] Re: Transaction Problem
Author Svein Erling Tysvær
Firebird use an optimistic locking system where only writers block writers (e.g. two transactions trying to do an update), writers don't block readers and readers don't block writers.

If you get an error message suggesting a lock conflict, then you are not just selecting from a table (well, unless you do something silly like specify WITH LOCK in your select query). Are you sure that no update statement is executed - not even by triggers?


-----Original Message-----
From: [] On Behalf Of sierraja2000
Sent: 4. november 2009 16:19
Subject: [firebird-support] Re: Transaction Problem

Hi, but the message is the same.

--- In, "Ann W. Harrison" <aharrison@...> wrote:
> sierraja2000 wrote:
> > ok the invoice number is generate on table, but if user1 is
> > view a invoice No. 1 and user2 need view then invoice No. 1
> > some time. This generate a dead lock. I want that multi-user
> > can view the some data. Sorry my english
> >
> There are no deadlocks on reading data, only on updates and
> deletes. Ready the paper Carlos suggested. It will show you
> how to create an auditable series of key values.
> >> In the IBO site, there is a paper that comments some solutions to the
> >> problem:
> >>
> >>
> >>
> Good luck,
> Ann



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