Subject Re: [firebird-support] How to convert 2.5 to 2.1 database
Author Helen Borrie
At 06:58 PM 1/12/2009, you wrote:
>Helen Borrie wrote:
>> At 05:51 PM 1/12/2009, Lester Caine wrote:
>>> Having had to rely on the gbak 'trick' a few times now where sites had to remain
>>> on FB1.5 but the new work is in FB2 then I would say that SOME means of
>>> backwards compatibility is essential?
>> Please don't try to start a feature discussion in this list, Lester. Take it to firebird-devel or firebird-architect, please.
>Actually Helen - I think it is quite important that people KNOW that there is a
>problem in using a facility that many USERS have probably relied on in the past?

Users who have relied on it have done so against all advice.

>A note added in the release notes is all very well ( I can't see anything about
>it at the moment? ),

It is always implicit in the General Notes section of release notes not to upgrade a database if you are not serious about it.

>but this information is something that actually makes me
>have to take more care if I want to start running FB2.5 up for testing.

More care = Good. ;-)

>All the
>machines here are FB2.1.2, but I have an FB1.5 gbak so that where I've pulled
>data from site - fixed thing and tidied up - I can then push it back to site if
>needs be. The fact that Ann was not aware of a problem would indicate that this
>may be something that has been overlooked?

Nope. In fact, it was Ann who discovered the trick and who has often suggested it during the Firebird era. And it was and is a trick. A hack you can try, but not rely on. It has *never* been a design aim to make databases "downgradeable". You got away with it for a while. Now you can't. (Actually, AFAIR, you can't use this trick to "downgrade" an ODS 11.1 db to ODS 10.x, either, because of metadata issues).

>So users who are now testing 2.5 - as this thread indicates - need to know the potential pitfalls rather than being caught out.

Why would we document a hack that happens not to work any more? If you think it's a pitfall, write an FAQ about it in your wiki.

Repeat, if you want to discuss changing this, take it to firebird-devel. I reckon you've left it far too late for Fb 2.5 release but go there if you want to be heard.


>Lester Caine - G8HFL
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