Re: SEQUENCE tracking

Thanks Jim, but I can't use AQ, because I want to broadcast messages. When a 'writer' thread writes a message, I want all 'readers' to read it.
I will implement a cleanup once in a while - that is not the problem.

The problem is that the 'readers' want to know what the've read, and what they haven't.
I could do it by locking the table, write (a short) message, and then unlock, but then it is outside my main transaction, and this is very dangerous.

Eran

"Jim Kennedy" <kennedy-family_at_attbi.com> wrote in message news:<aPhn8.104077$af7.56191_at_rwcrnsc53>...
> use advanced queuing.
> Jim
> "Eran Dvey-Aharon" <eran_at_prosight.com> wrote in message
> news:ce3f1689.0203240204.5038600f_at_posting.google.com...
> > Hi all !
> >
> > I have the following problem :
> > Many processes/threads write into a common table, that I use as a
> > messaging queue. I use sequences, and that way the writers don't block
> > each other.
> >
> > I also have many readers. The readers should be able to read all the
> > entries that they didn't read before.
> >
> > How can I accomplish that ?
> > To those of you that don't understand the problem : if the reader
> > reads messages 1,2,3,4,6,7,8 it can't assume that messages # 5 will
> > never be written.
> > It might be in the process of writing.
> > I also don't want to add any locks to this scheme. The readers should
> > read only the new committed messages, and the writers should be able
> > to write without being blocked.
> >
> > Any ideas ?
> >
> > Eran
Received on Sun Mar 24 2002 - 14:55:49 CET