Subject Re: Database for images
Author Adam
> You must remember, we use FreeBSD - a very different beast to
Windows and
> Linux. We can take a filesystem snapshot, and spend as much time as
we like
> doing a filesystem copy of the .fdb from the server to anywhere, and
> Firebird can happily continue on it's version of the filesystem.

That would be a key to doing it that way. I do not know enough about
BSD filesystems, but for that to work the filesystem must be
internally doing its own version of MGA (maintaining a delta file or
something like that). Otherwise you will end up with all sorts of
funny business. Records in the data page written by transactions that
don't exist yet in the TIP and other fun things.

On file systems like NTFS, you would be lucky to have a successful backup.

As Glebas points out, a database with a table that size would need FB
2, and NBackup allows you to put the database into a backup mode,
where any deltas are written to another file to be merged later. You
could conceivably put the database in this mode, use rsync to send the
deltas (which should be relatively few) and then put it back into
normal mode. The added advantage is that it would work on any platform
which supports nbackup.

I would still prefer the approach I suggested of keeping images out of
the database if for no other reason that it allows other future
applications to process the images without having to write some
complicated interface. If access control is the only issue, it is
easily resolved by file system permissions that allow fbserver to see
what the user can not under their own account.