Subject Re: [firebird-support] Migration Guide for Firebird 1.5.3 to 2.5.4
Author Helen Borrie
At 11:42 p.m. 22/07/2015, 'stwizard' stwizard@... [firebird-support] wrote:

>Greetings All,
>I�m needing to get underway way with preparing my Firebird 1.5.3 database for migration to 2.5.4.

Firebird 1.5.3 to 2.5.4 is not a migration, it is an upgrade. Actually, you don't even *absolutely need* to upgrade your databases to run them under 2.5.4. But if you have old application code, you are likely to bump into a few problems if deprecation warnings have been ignored in the past. Our guys have spent the past 15 years cleaning horse manure out of the Firebird engine. And, of course, a, ODS 10.1 database can't take advantage of many of the newer features that came for ODS 11.0, 11.1 and 11.2.

>Is there any documentation available that discusses what all needs to be looked at before backing up the database in 1.5.3 and restoring to 2.5.4?

Yes - the release notes for versions 2.0, 2.1 and 2.5, all read in order. Check the compatibility sections of them all. You will find that particular documentation for v.2.0 and 2.1 in the same, separate document (Migration and Installation Notes). You'll find all of them at

>Possibly a migration guide?

You don't need a "migration guide", per se, because it isn't a migration. But I did call it that for the jump from 1.5 to 2.0 and particularly to 2.1, because the metadata character set changed from ascii to unicode_fss. Make sure you read up on that particular thing, otherwise it will bite you. But - tip - if you do a careful reading of the release notes, you will discover that gbak restore has a switch so that your restored database will have the metadata charset updated for you. If you have check constraints that involve characters, you'll need both switches.

Do I need to advise you to make plenty of backups as you go? Most likely they'll end up being redundant but then there is Murphy's Law.