Subject Re: Maximum Capacity
Author Frank Emser <>
--- In, Paul Schmidt <pschmidt@i...> wrote:
> > 1.) Obvious solution: Incremental backups come to my mind.
> > 2.) The backup-process could probably record the changes done to the
> > database whilst it was backed-up as well.
> Making a user wait 11 days for a restore, when it
> costs the company $100,000 per hour that the system is down, is
> unacceptable.
Agreed. But if it is the restore-time you are worrying about,
I would recommend to create a hard-disk-mirror-system as backup:
You could create a shadow located on a second hard disk set or you
leave rebuilding the mirror to some RAID 1-hardware.
I confess, there is a samll downtime necessary at the moment when you
replace the mirror-hard-disk-set with fresh hard-disks.
Of course, it sounds completely unconventional to use hard disks as
store-away back-up-media. But it is not my idea anyway. I read about
it in the (german) computer magazin c't 1/2003, p.136.
The basic idea is that a DLT-IV-tape with 40 GByte capacity now costs
about 60-70 Euro, the same as a 80-120 GByte disk.

> The idea was to illustrate that practical limits can be far
> more limiting, then the theoretical limits.
You are right. But I think that especially the backup/restore-problem
can be circumvented and is therefore not the very best example.
I really would like to know how "they" backup this famous 980
GB-firebird-database mentioned already several times before.

> Of course a 32TB database used for day to day operations would
probably be
> too slow, so it makes more sense to use a small database for day to day
> operations, and then monthly run a batch update to the "big"
database, and
> run your summary reports after that, so maybe you don't backup the big
> database every day, because your not updating it every day. This
would be
> much more practical.
As far as I can tell now, I would at least hesitate to create with
firebird (or any other database system...) a DVD-movie database which
not only stores the description and other information about the
movies, but as well stores the dvd-movies themselves as BLOBs. ;-)

Kind regards
Frank Emser