We have a centralized database cluster (an Oracle RAC), which serves virtually all of our applications on behalf of all of our clients.
We have always been very reluctant and very careful when making any changes, as any downtime could affect everyone.
Consequently, we have only applied emergency patches. By our definition, the need for emergency patches outweighs the risk of the potential side-effects. We only do this when needed - a very rare event.
We were purchased by a much larger company. Now, as we continue to integrate with a larger organization, the company is hinting that we must get prepared to apply database patches on a regular basis - at least quarterly, and perhaps monthly.
I'm faced with trying to find the time to regression test several dozen applications periodically, then releasing the database updates off-hours. I estimate that it would take about a week of dedicated testing by at least 3 testers to accomplish these regression tests. And of course I simply don't have that kind of time in the schedule, so I'm currently negotiating for additional headcount.
I've spoken with other groups which were previously acquired by the parent company. They don't quite have the same problem, as they support only a single application each.
I'm wondering if others have faced a similar requirement, and if so, how you have handled it?
Do you steal time from other projects to test the effects of periodic database upgrades?
Do you have dedicated testers whose sole responsibility is to test infrastructure upgrades, rather than application changes?
Or something else?
Thanks for your help!