Frequency of compressing/repair replicated databases

[Bob Alston]

I have a system built using Access replication. After some initial
problems dealing with memo fields, it now seems to be working well.

I am curious as to how frequently others Compress & Repair replicated
databases?

Bob

[David W. Fenton]

Bob Alston <bo********@yahoo.comwrote in
news:Hr****************@newsfe08.iad:

I have a system built using Access replication. After some
initial problems dealing with memo fields, it now seems to be
working well.

I am curious as to how frequently others Compress & Repair
replicated databases?

First off, is your app split, with your data tables in one MDB that
is replicated, and all your forms/reports/etc. in a separate MDB
that is *not* replicated? If not, that's much more important to fix
than worrying about how often you compact.

Compacting a replicated database is a bit more dangerous than
compacting non-replicated databases. This is because certain minor
corruptions that are easily repaired by a compact in a
non-replicated database cause a replicated MDB to lose replicability
(which means it can't synch with the other members of its replica
set any longer). Unfortunately, there's no way to tell if you have
this kind of problem -- it is only revealed after the fact, when
replicability is lost.

Thus, I'd recommend regular maintenance compacts on a replicated
back end at a lower frequency than on a non-replicated back end. If
you're compacting your non-replicated MDB every day, I'd recommend
every week for a replicated MDB. Keep in mind that the other
replicas in teh replica set function as backups, so you're not in as
much danger of data loss as you are with a single non-replicated
MDB. And if you implement a replica farm, you can have very good
coverage in terms of recovery from the loss of any single replica.

--
David W. Fenton http://www.dfenton.com/
usenet at dfenton dot com http://www.dfenton.com/DFA/

[Bob Alston]

David W. Fenton wrote:

Bob Alston <bo********@yahoo.comwrote in
news:Hr****************@newsfe08.iad:

>I have a system built using Access replication. After some
initial problems dealing with memo fields, it now seems to be
working well.

I am curious as to how frequently others Compress & Repair
replicated databases?

First off, is your app split, with your data tables in one MDB that
is replicated, and all your forms/reports/etc. in a separate MDB
that is *not* replicated? If not, that's much more important to fix
than worrying about how often you compact.

Compacting a replicated database is a bit more dangerous than
compacting non-replicated databases. This is because certain minor
corruptions that are easily repaired by a compact in a
non-replicated database cause a replicated MDB to lose replicability
(which means it can't synch with the other members of its replica
set any longer). Unfortunately, there's no way to tell if you have
this kind of problem -- it is only revealed after the fact, when
replicability is lost.

Thus, I'd recommend regular maintenance compacts on a replicated
back end at a lower frequency than on a non-replicated back end. If
you're compacting your non-replicated MDB every day, I'd recommend
every week for a replicated MDB. Keep in mind that the other
replicas in teh replica set function as backups, so you're not in as
much danger of data loss as you are with a single non-replicated
MDB. And if you implement a replica farm, you can have very good
coverage in terms of recovery from the loss of any single replica.

Thanks for the suggestions. Yes I do have a separated FE and BE. Of
course I only replicate the BE.

Recently I compressed and repaired the three sets of replicas in farms
on each of three servers. It reduced their size considerably.

I am concerned about the replicas on the laptops where I have no
schedule for compress and repair.

I trhink I recall once hearing about someone creating a second replica
on a laptop as a backup. I wonder if that would be something to do just
before doing the compress/repair in case I lost ability to replicate.
YOur thoughts?

Bob

[David W. Fenton]

Bob Alston <bo********@yahoo.comwrote in
news:V%**************@newsfe04.iad:

I am concerned about the replicas on the laptops where I have no
schedule for compress and repair.

Chances are good that this is not going to matter a lot.

I trhink I recall once hearing about someone creating a second
replica on a laptop as a backup. I wonder if that would be
something to do just before doing the compress/repair in case I
lost ability to replicate. YOur thoughts?

Most of my replicated apps do a synch with a backup replica upon
closing as a matter of course.

--
David W. Fenton http://www.dfenton.com/
usenet at dfenton dot com http://www.dfenton.com/DFA/