Subject RE: [IB-Architect] Backward compatability with previous versions of gdb files
Author Claudio Valderrama C.
> -----Original Message-----
> From: Dominique Louis [mailto:dlouis@...]
> Sent: Domingo 30 de Abril de 2000 16:27
>
> Bill Karwin wrote:
> >I don't
> > think it's too complex or unreasonable to require a gbak&restore to
> > migrate one's databases to IB6 (dialect 1).
>
> I totally agree, though it's just a litte more hassle and most people want
> less hassle in general even if it compromises the integrity of their
> database.

If you think a bit, which are the people that will come from IB5? Probably
old customers. *Probably* these people already know how to use gbak. Not
very terrible to use it once more. The only drawback is in a few specific
cases, gbak may not be able to copy the data on one of the tables in the
IB4/IB5 backup to the gdb on the new ODS_10, but these cases are not
frequent.

On the other side, newcomers will use a dialect 1 or 3 databases (depending
on whether they are tied to the Borland Database Enema or not) but always on
ODS_10, because they will be creating their databases for the first time on
IB6.

Hope I won't be flamed to mention MsSql's case. ;-) MickeySoft created a
big set of scripts to upgrade Sql65 to Sql70 databases "in place". I ran the
script on my machine, with a few tables and databases, only a few Megabytes.
I had to make some adjustments to the Master db to avoid the script exiting
with an error message. The script took all the evening and also, it left a
lot of trash in some directories inside the new installation, that I never
have been sure if I can delete or not. In a "real" database, it would have
took days. The very few big customers I have (the ones that can and want to
pay MickeySoft) simply backed up, uninstalled Sql65, installed Sql70 and
after 40 reboots, they began restoring their data. The net result: much
faster and much more reliable.

Writing a tool or script that migrated from ODS_8 or ODS_9 to ODS_10 in
dialect 1 seems to be not a big problem. However, writing the tool to
convert to dialect 3 is no joke (comments welcome), because there are
several decisions that need to be planned. A blind conversion is IMHO a
direct call for disaster.

Just a personal thought.

C.