Re: Simple Upgrade questions

Brian Peasland <dba_at_remove_spam.peasland.com> wrote:

>
>These scripts are found in $ORACLE_HOME/rdbms/admin.

From what you explain below, it is the $ORACLE_HOME of the new version which is meant here.

>
>This is incorrect. Upgrading does not replace any binaries or libraries.

THAT is the answer I was looking for.

>You currently have software in your 8i ORACLE_HOME. You will need to
>install the 9i software in a new, 9i ORACLE_HOME. At this point, you
>have different binaries and library files installed in two distinctly
>different directories. You can also apply the 9.2.0.4 patchset at this
>time if you want, or you can do the patch later. Next, you will be
>upgrading your 8i db. This involves shutting down the db and then
>starting it up with the 9i HOME and then running an upgrade script. You
>can do this manually or you can do this with the Upgrade Assistant.
>After the database is upgraded and you are running on the 9i HOME, you
>can use the OUI to safely remove the 8i HOME software.

This short, precise description was what I was missing.

>Please make sure that you do the following before you proceed:
>
>1. Read the Oracle 9i Migration Guide (http://tahiti.oracle.com). A
>thorough understanding of this document is essential for pain-free
>migration to the new version.

I bet that one has to go through a miriad of details obfuscating the plain, general procedure. I need to understand the concept first, then I will go into details. Thank you for explaining me what seems to be too obvious to others.

>2. Take a backup *before* and *after* you've upgraded. This way, you can
>revert to the database as it existed right before the upgrade. And a
>recovery 3 days after the upgrade can be accomplished without having to
>do the upgrade all over again, and trying to find some way to get all of
>your transactions in there as well.

The DB is "always" backed up. Archive-logs go to tape every 15 min (through a HSM archiving system). Rman driven full backups take place weekly, besides cold backups on Sundays too. Exports are done dayly.

>3. Test, test, test. Test the upgrade process itself on a test database
>before you even look at production. Test your application against the
>upgraded database.

Of course. Actually, we do have a 9i version of the DB on a test environment, running in parallel with the 8i Version. The 9i Version was a full import. But in the production system we want to "upgrade". So we will rehearse upgrading in the test system, now that I understood the basics. It was not clear to me that the upgrade procedure assumes that the binaries of the new version are already installed. So there is no such thing like upgrading Oracle (i.e. the software); it is the DB alone what is going to be upgraded.

At least the DB files are going to be upgraded in place (avoiding having to deal with two copies).

Thanks
Rick Denoire Received on Mon Sep 15 2003 - 15:44:07 CDT