Best Practices to Use Database Upgrade Assistant

I’m going to upgrade one of our main databases with DBUA (Database Upgrade Assistant), and I take some notes to provide a smooth upgrade. Upgrading your database with DBUA seems a very easy and automated task but there are three important points you should consider when updating:

  • Downtime: You would probably like to keep downtime to a minimum
  • Errors while upgrading: It’s not possible to re-run DBUA if an error is encountered mid-upgrade!
  • Performance Degradations: Most of the upgrade problems appear as performance degradations after the upgrade operation completed

So you need to carefully evaluate, plan, configure, test and implement the upgrade.

PLAN: First of all, I recommend you to visit the upgrade guides and plan all steps of the upgrade process:

Upgrade Advisor: Database from 9.2 to 11.2 [ID 264.1]
Upgrade Advisor: Database from 10.2 to 11.2 [ID 251.1]

RTFM: Although everyone says the same, we all intend to pass this step. Read the manuals before it’s too late 🙂

Very important and useful documents:

Oracle 11gR1 Upgrade Companion [ID 601807.1]
Oracle 11gR2 Upgrade Companion [ID 785351.1]

Use Internet Explorer to read upgrade companion documents (because they are interactive and requires IE) and don’t forget to check “behavior changes”!