If you have another table with a record for each client then you can record
the last journal id processed by each client. Then have a purge process
that removes old journal entries based on the min(id).
The problem with this is cross db transactions. What happens if the cleint
read the journal, updates the last read pointer and then write's to it's db
and fails? Where are you going to commit the trannie's? The only way to
get full proff commits across >1 db is to use some sort of 2 phase commits -
eg, mts.
>From: "Donovan J. Edye" <[EMAIL PROTECTED]>
>Reply-To: [EMAIL PROTECTED]
>To: Multiple recipients of list delphi <[EMAIL PROTECTED]>
>Subject: RE: [DUG]: Interbase, TIBEvents.....
>Date: Thu, 3 Feb 2000 13:28:46 +1100
>
>P,
>
> > Rather than just going to the end, you probably need to keep track of
>the
> > last thing you got and then look for next one. This way, you will keep
> > add's and deletes and changes to the same record in a sensible order.
>
>Yep. But say as per my example when the system starts "clean". Do I go and
>look at the first record? If so then that would assume that the journal
>table would have to be purged. Sure would make things easier if you were
>able to pass data back with the event.....
>
>
>------------------------------------------------------------------------
>--Donovan
>Donovan J. Edye [www.edye.wattle.id.au]
>Namadgi Systems, Delphi Developer
>Web: www.namsys.com.au E-Mail: [EMAIL PROTECTED]
>Voice: +61 2 6285-3460 Fax: +61 2 6285-3459
>TVisualBasic = Class(None);
>------------------------------------------------------------------------
>
>
> > -----Original Message-----
> > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On
> > Behalf Of Peter G Jones
> > Sent: Friday, 4 February 2000 02:11
> > To: Multiple recipients of list delphi
> > Subject: RE: [DUG]: Interbase, TIBEvents.....
> >
> >
> > Rather than just going to the end, you probably need to keep track of
>the
> > last thing you got and then look for next one. This way, you will keep
> > add's and deletes and changes to the same record in a sensible order.
> >
> >
> > >From: "Donovan J. Edye" <[EMAIL PROTECTED]>
> > >Reply-To: [EMAIL PROTECTED]
> > >To: Multiple recipients of list delphi <[EMAIL PROTECTED]>
> > >Subject: RE: [DUG]: Interbase, TIBEvents.....
> > >Date: Thu, 3 Feb 2000 12:29:09 +1100
> > >
> > >P,
> > >
> > >So effectively when the event arrives go and have a look at the
> > last entry
> > >in the table?? Would it not be a case that records could be posted to
>the
> > >table and the events dispatched and because they are
> > sequentially queued in
> > >the delphi app things may get out of sync??
> > >
> > >Eg.
> > >
> > >In IB
> > >
> > >Add Rec 1 Fire Ev1
> > >Add Rec 2 Fire Ev2
> > >Add Rec 3 Fire Ev3
> > >
> > >In Delphi
> > >
> > >Gets Ev1 and processes it. Does last and gets Rec1.
> > >However by this time Ev2 & Ev3 have arrived and are queued
> > >Processe Ev2. Goes to last and gets Rec3!!!
> > >Process Ev3. Goes to last and gets Rec3!!!
> > >
> > >Is the above correct???
> > >
> >
> >------------------------------------------------------------------------
> > >--Donovan
> > >Donovan J. Edye [www.edye.wattle.id.au]
> > >Namadgi Systems, Delphi Developer
> > >Web: www.namsys.com.au E-Mail: [EMAIL PROTECTED]
> > >Voice: +61 2 6285-3460 Fax: +61 2 6285-3459
> > >TVisualBasic = Class(None);
> >
> >------------------------------------------------------------------------
> > >
> > >
> > > > -----Original Message-----
> > > > From: [EMAIL PROTECTED]
>[mailto:[EMAIL PROTECTED]]On
> > > > Behalf Of Peter G Jones
> > > > Sent: Friday, 4 February 2000 01:03
> > > > To: Multiple recipients of list delphi
> > > > Subject: Re: [DUG]: Interbase, TIBEvents.....
> > > >
> > > >
> > > > Create a journal table and add a record to that with the
> > > > key/table name of
> > > > the record to look for. Then call your event.
> > > >
> > > > Because event's can be lost, this also helps you catch up with
> > > > stuff you may
> > > > have missed.
> > > >
> > > >
> > > >
> > > > >From: "Donovan J. Edye" <[EMAIL PROTECTED]>
> > > > >Reply-To: [EMAIL PROTECTED]
> > > > >To: Multiple recipients of list delphi <[EMAIL PROTECTED]>
> > > > >Subject: [DUG]: Interbase, TIBEvents.....
> > > > >Date: Wed, 2 Feb 2000 11:04:28 +1100
> > > > >
> > > > >G'Day,
> > > > >
> > > > >TIBEvents is a great notifaction scheme, however..... I can't
> > > > see a way to
> > > > >actually pass some data back to the interested applications.
> > Yes, so a
> > > > >record has changed in the table. However the interested
> > > > application has no
> > > > >clue which one. It would be more helpful if I could somehow pass
>say
> > >the
> > > > >record id back to the interested application. That way it could
> > > > go directly
> > > > >to the specified record instead of attempting to determine
> > which one it
> > > > >was.
> > > > >
> > > > >Any ideas on how I could do that??
> > > > >
> > > > >TIA
> > > > >
> > > >
> > >
> >
> >------------------------------------------------------------------------
> > > > >--Donovan
> > > > >Donovan J. Edye [www.edye.wattle.id.au]
> > > > >Namadgi Systems, Delphi Developer
> > > > >Web: www.namsys.com.au E-Mail: [EMAIL PROTECTED]
> > > > >Voice: +61 2 6285-3460 Fax: +61 2 6285-3459
> > > > >TVisualBasic = Class(None);
> > > >
> > >
> >
> >------------------------------------------------------------------------
> > > > >
> > > > >-----------------------------------------------------------------
> > > > ----------
> > > > > New Zealand Delphi Users group - Delphi List -
> > >[EMAIL PROTECTED]
> > > > > Website: http://www.delphi.org.nz
> > > >
> > > > ______________________________________________________
> > > > Get Your Private, Free Email at http://www.hotmail.com
> > > >
> > > > ------------------------------------------------------------------
> > > > ---------
> > > > New Zealand Delphi Users group - Delphi List -
> > [EMAIL PROTECTED]
> > > > Website: http://www.delphi.org.nz
> > > >
> > >
> > >-----------------------------------------------------------------
> > ----------
> > > New Zealand Delphi Users group - Delphi List -
>[EMAIL PROTECTED]
> > > Website: http://www.delphi.org.nz
> >
> > ______________________________________________________
> > Get Your Private, Free Email at http://www.hotmail.com
> >
> > ------------------------------------------------------------------
> > ---------
> > New Zealand Delphi Users group - Delphi List - [EMAIL PROTECTED]
> > Website: http://www.delphi.org.nz
> >
>
>---------------------------------------------------------------------------
> New Zealand Delphi Users group - Delphi List - [EMAIL PROTECTED]
> Website: http://www.delphi.org.nz
______________________________________________________
Get Your Private, Free Email at http://www.hotmail.com
---------------------------------------------------------------------------
New Zealand Delphi Users group - Delphi List - [EMAIL PROTECTED]
Website: http://www.delphi.org.nz
