Before I run off and figure out how to syncronize a "backup" database
with a live one, I was wondering if anyone had any pointers on 
implementing a delayed syncronization way of backing up a database
while it's live.  I'd really like to be able to only transfer over
modified rows, rather than the entire database.

Any clues, pointers that could help me out?

thanks,
-Alfred

Thu, 10 Aug 2000 15:25:12 -0700
Alfred Perlstein <bright@wintelcom.net>
Live incremental backups?
At 15:25 10/08/00 -0700, Alfred Perlstein wrote:
>Before I run off and figure out how to syncronize a "backup" database
>with a live one, I was wondering if anyone had any pointers on 
>implementing a delayed syncronization way of backing up a database
>while it's live.  I'd really like to be able to only transfer over
>modified rows, rather than the entire database.
>

My *guess* is that the WAL should add a few options here - especially for
backup. However, if your replication is only partial, it may not help as much.

On other system I have used, you 'truncate' the WAL periodically and save
it is part of the backup. These pieces of WAL can be applied to a prior
copy of the database to produce a version of the DB at the time the WAL was
truncated.

Obviously this requires a little more than just the WAL, but it might be
the right way to go in the future for on-line backup and whole-database,
read-only replication.


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Fri, 11 Aug 2000 11:02:41 +1000
Philip Warner <pjw@rhyme.com.au>
Re: Live incremental backups?