Re: [Firebird-devel] ODS 9 corruption bug...

[Mike N. <ta...@al...>]

Ann W. Harrison wrote:
> At 07:53 PM 5/2/2001 +0200, Mike Nordell wrote:
>
> I [Ann] said:
> > > I have
> > > a database created by 5.6 that my copy of Firebird won't read.
> > > Given a day or so, I'll probably know why.  Anybody else
> > > want to take a hack at it?
>
> At 07:53 PM 5/2/2001 +0200, Mike Nordell wrote:
>
> >I only have one question: Why?
>
> and proceeded to ask more questions.

Which connects to that single question to the amount that it still is one
question: Why.

>
> >The native ODS of Firebird 1 is 10, why even bother reading earlier stuff
> >when they can/should solve it by backup from x.y and restore using
Firebird
> >1 (ODS 10).
>
> Right.  But it's a damn nuisance that you can't run Firebird and
> IB5.x at the same time.

It is? I'd say it's damned good we can't! Had I ever heard of a potential
problem , this would be it. Running both at the same time would create a
nightmare I'm sure I don't want to be part of.

I might also be more specific to say "I think we should be able to read
earlier versions, but there's no way in ... we should write them". Perhaps
that better explains my standpoint and also possibly invalidates some of the
comments (sorry for not being complete, I'll try to not let it happen
again).

> Lots of people uninstall IB when they
> install Firebird.  Then they realize that they forgot to convert
> some database (isc4, anyone?) and the mad scramble is on to find
> the V5 media, which they had just three years ago and must be here
> somewhere...

OK, this makes sense. But wouldn't "mounting" that one read-only and
allowing backup of it take care of the problems? Besides, what do you (all)
think about renaming that DB file for "new" or future installations as to
not add to the confusion? What about "fb1secur.gdb" (to keep it to 8+3 for
reasons I still don't understand, "FB1_Security.gdb" would in my world be a
more currect name?

> >If someone want to stay file-compatible with x.y, why even bother using
> >Firebird 1.0 against that file???
>
> Think of it as a bridge, not a bunker.

Since I've been dealing with multi-version on-disk format apps for some
years now I think I have a rather good idea of what's needed and what we're
dealing with. I might be wrong re. DB files, but I think not.

My solution has earlier been:

1. Allow reading of old data.
2. Allow saving as (only) new data (i.e., conversion).

If any steps took place between 1 & 2 that changed the data, either save it
as the new version or be rid of it.

What we perhaps could provide is conversion apps, to rid the backup/restore
cycle, but I still think we should only write our current ODS format.

/Mike