SEO

(Sorry for this DB2 topic in the Informix group. I've cross-posted to the
DB2 group and set follow-up to the DB2 group, as well.)

Discussion history: I made a grumpy statement about DB2's inability to
restore across endianness.

On Sun, 17 Feb 2008 19:47:47 -0500, Serge Rielau wrote:
> I fail to see what one has to do with the other. Intel 32 to Intel 64 is
> supported in DB2. In fact there is no need for a backup/restore at all.
> You simply flip the instance to 64 bit.

Yes, but backups have other use cases, as well. Like:

- We would sleep slightly more comfortably if we knew that we could
easily restore our pSeries-DB2 data to an x86_64 server in case
the pSeries server blew up: x86_64 hardware is easier to get
hold of in a hurry.

- Production system is on an x86 server which has run out of
hardware upgrade options, so we want to move the database
to a pSeries LPAR. - So we might as well use the TSM system's
bytes instead of having to export all the data to files first.

- Or the other way around: The pSeries hardware is somewhat old
and overloaded. So let's move the database to a shining new
x86_64 host. Again: TSM already has all the data, so why not
use it.

There are also situations where development is done on - e.g. x86_64, and
(test+)production is on the expensive equipment, and in some cases, it
makes sense to use the backup/restore system to move the data. db2look
+db2move isn't very nice to work with because:
- I've seen situations where db2look seemingly produced DDL
which couldn't be used (wrong order of DB structure creations).
- db2move seems to lock quite a bit, and db2move-based dumps
don't guarantee inter-table consistency.

> You hardly expect the DBMS to punish every I/O by
> normalizing integers to one scheme or the other just in the unlikely
> someday endianness will be changed.

I know that this would add to the explosion-of-parameters danger, but:
Why not make it an option to the BACKUP DATABASE command?

--
Regards,
Troels Arvin <troels@arvin.dk>
http://troels.arvin.dk/

Troels Arvin wrote:
> (Sorry for this DB2 topic in the Informix group. I've cross-posted to the
> DB2 group and set follow-up to the DB2 group, as well.)
>
> Discussion history: I made a grumpy statement about DB2's inability to
> restore across endianness.

[...]

> There are also situations where development is done on - e.g. x86_64, and
> (test+)production is on the expensive equipment, and in some cases, it
> makes sense to use the backup/restore system to move the data. db2look

Although I understand the pain, I don't see great future here... With
increasingly regulatory compliance you surely don't want to put your data from
production servers in front of the eyes of the developers...

Products like Optim (from Princeton Softech which was bought by IBM recently)
seem to have a great expansion opportunity.

Regards,

--
Fernando Nunes
Portugal

http://informix-technology.blogspot.com
My email works... but I don't check it frequently...