Subject RE: [firebird-support] Looking for some suggestions...Vertical market apps
Author Myles Wakeham
> On 02-Aug-2004 07:16:58, Alan McDonald wrote:
> > a. Where do you store the version number of the DB? Is this in data in
> > the database or somewhere in meta data?
> in it's own one record table, called version, minor, major etc fields

OK, but if your customer lost all the data in the database (including these
records), how would you ever know what to upgrade from again? I guess I'm
kinda answering my own question here - put this information somewhere
outside of the database, but be sure to include a copy of it somewhere. I
guess this could be stored redundantly with the application (ie. 'Last DB
Version used' or something like that).

> > c. You mentioned that there is no need to unload the data from the
> > database when the schema is altered. Am I to assume, that statements
> > 'ALTER TABLE', etc. will not affect data stored in the tables in
> >
> only if you alter table drop field... you'll loose the data in that field.
> If you want to change the datatype, then depending on how bad you have to
> it, you'll crea a temp field, update that field from the old field, drop
> old one, create a new one and update the new on from the old one, then
> that temp one. Generally I don't need to do this. If you are adding fields
> you don't have to worry at all.

OK, I can work with that. The current database I am using doesn't let me
DROP fields anyway, so I guess old habits here won't have to die afterall :)


Myles Wakeham
Director of Engineering
Tech Solutions US, Inc.
(480) 451-7440