Oracle Database RU and RUR Recommendations and Facts

Well … another post about RU and RUR patches. But after having multiple discussions personally, via web conferences, in conference calls and of course on Twitter I think some clarifications may be helpful. Below you’ll find Oracle Database RU and RUR recommendations and facts. At least some of them …

Oracle Database RU and RUR Recommendations and Facts

First of all, you will find more information in several blog posts about RU (Release Update) and RUR (Release Update Revision) patches:

• PSU or BP? Patch Set Update or Bundle Patch? RUR or RU? (May 12, 2017)
• More Information about RU and RUR patches for Oracle 12.2 (Jul 19, 2017)
• Applying the first RU to Oracle Database 12.2.0.1 (Jul 20, 2017)
• Download Assistant for RUs, RURs, BPs, PSUs, Patch Sets and Releases (Oct 13, 2017)
• Are OJVM patches included in the Oracle 12.2 RU / RUR (Oct 20, 2017)
• Differences between PSU / BP and RU / RUR (Oct 24, 2017)

In addition to these posts I’d like to clarify some interesting facts.

Five Facts

Fact 1 – There MAY be two RURs –

In Differences between PSU / BP and RU / RUR I mentioned already that RURs usually will get released every quarter. USUALLY and QUARTER are the important words regarding RURs.RURs contain the previous RU plus new security fixes and maybe some important regression fixes in addition. They MAY be released every quarter.

Example RUR containing the previous RU plus ONLY NEW security and regression fixes in addition

Additionally our goal is to release two RURs on top of one RU at the same schedule as RUs. But there’s no guarantee for it. This means, we may release an RUR earlier if something really important happens. We may also release a third RUR on top of an RU if there’s a need for it.

Fact 2 – An RU is a patch – and not an upgrade

I love upgrades. Of course I do as otherwise I wouldn’t do this upgrade and migration job for almost 10 years now in Oracle’s Development organization. But an RU is just a patch bundle. Despite the fact that it will increase the release number on its second digit. Remember that we will change the release numbering as well. Therefore an RU is not an upgrade. See Differences between PSU / BP and RU / RUR and My thoughts about the new Oracle Database Release Schedule.

It’s a patch – not an upgrade.

Fact 3 – RUs are cummulative

It’s the similar to the Bundle Patches for previous releases. If you apply an RU it will contain automatically all previous RUs for this releases. For instance, if you will apply 18.4.0 you’ll automatically have 18.2.0 and 18.3.0 included. See Differences between PSU / BP and RU / RUR for further details.

Fact 4 – Same tasks to apply RU or RUR

I’d just like to point this out: There’s zero difference in work and tasks, regardless if you apply an RU or RUR.

Fact 5 – You can download OJVM patches separately

You can either take an RU and download the OJVM patch separately or you may download the Combo patches containing both in separate subdirectories. See Are OJVM patches included in the RU /RUR? for further details.

Please see this MOS Note explaining the Conditional Install for further clarification and guidance.

Two Recommendations

Recommendation 1 – Go with RUs

Please use the RUs. RURs are just meant for special cases for customers who want only the security fixes for the next 6 months. Don’t be afraid of Optimizer behavior changes: those are disabled by default in RUs. You will need to enable them. If an RU contains such fixes you’ll find this paragraph in the patches’ readme:

“This patch introduces fix control for one or more fixes contained herein. These fixes are disabled by default and will have to be explicitly enabled via alter session/system commands to persist in pfile/spfile as appropriate”

If this paragraph is not present in the readme, no such fix is included.

Recommendation 2 – Apply RUs every quarter – be agile!

You may now say: “Well Mike, we are happy if we can apply it every 6 months.” And in fact, that’s what many customers tell me for ages. I can see the point of it. Patching is neither fun nor pleasureful work. It’s a tough topic. Especially in cases where you take care on many many database environments at the same time and don’t use Oracle Multitenant.

But please consider three facts:

• RUs are not BPs anymore. Optimizer behavior changing fixes are disabled by default. See Differences between PSU / BP and RU / RUR as well.
• Get the most recent security fixes asap. If not, Google this or that.
• Remember: Our release and patching model will become more agile. You should adopt it. Become more agile as well.

–Mike