For years, Oracle used the same mechanism for database versioning. A major version, represented by the first number. And then a release number, 1 for the very first edition, and a mature and reliable release 2 for production databases. Both of them having patchsets (the last number) and regular patchset updates (the date optionally displayed at the end) to remove bugs and to increase security. Jumping from release 1 to release 2 required a migration as if you were coming from an older version. Recently, Oracle broke this release pace to introduce a new versioning system based on the year of release, like Microsoft and a lot of others did. Patchsets are also replaced by release updates. Quite obvious: it’s been a long time patchsets have become complete releases. Lots of Oracle DBAs are now in the fog, and as a result, could take wrong decision regarding the version to choose.
A recent history of Oracle Database versioning
Let’s focus on the versions currently running on most of customer’s databases:
- 18.104.22.168: The terminal version of 11gR2 (long-term). 4 is the latest patchset of the 11gR2, there will never exist a 22.214.171.124. If you install the latest PSU (Patchset update) your database will precisely run on 126.96.36.199.191015 (as of the 29th of November 2019)
- 188.8.131.52: The terminal version of 12cR1 (sort of long-term). A 184.108.40.206 existed but for a very short time
- 220.127.116.11: first version of 12cR2 (short-term). This is the latest version with old versioning model
- 18c: actually 18.104.22.168 – first patchset of the 22.214.171.124 (short-term). You cannot apply this patchset on top of the 126.96.36.199
- 19c: actually 188.8.131.52 – terminal version of the 12cR2 (long-term). The next version will no more be based on 12.2 database kernel
18c and 19c also have sort of patchset but the name has changed: we’re now talking about RU (release update). RU are actually the second number, 18.8 for example. Each release update can also be updated with PSUs, still the last number, for example 184.108.40.206.191015.
Is there a risk to use older versions?
Actually, there is no risk using 220.127.116.11 and 18.104.22.168. These versions represent almost all the Oracle databases running in the world. Few people already migrated to 12.2 or newer versions. The risk is more related to the support provided by Oracle. With premier support (linked to the support fees almost every customer pay each year), you have limited access to My Oracle Support. Looking up for something in the knowledge database is OK, downloading old patches is OK, but downloading newest patches will no more be possible. And if you open a SR, the Oracle support team could ask you to buy extended support, or at least to apply the latest PSU you cannot download. If you want to keep your databases fully supported by Oracle, you’ll have to ask and pay for extended support, as far as your version can still be supported with this kind of support. For sure, 11gR1, 10gR2 and older versions are no more eligible for extended support.
Check this My Oracle Support note for fresh information about support timeline: Doc ID 742060.1
Should I migrate to 12.2 or 18c?
If you plan to migrate to 12.2 or 18c in 2020, think twice. The problem with these versions is that premier support is ending soon: before the end of 2020 for 12.2 and in the middle of 2021 for 18c. It’s very short and you probably won’t have the possibility to buy extended support (these are not terminal releases), you’ll have to migrate to 19c or newer version in 2020 or 2021.
Why 19c is probably the only version you should migrate to?
19c is the long-term support release, meaning that premier support will last longer (until 2023) and also that extended support will be available (until 2026). If you plan to migrate to 19c in 2020, you will benefit from all the desired patches and full support for 3 years. And there is a chance that Oracle will also offer extended support for the first year or more, as they did for 11.2 and 12.1, even it’s pure assumption.
How about the costs?
You probably own perpetual licenses, meaning that the Oracle database product is yours (if you are compliant regarding the number of users or processors defined in your contract). Your licenses are not attached to a specific version, you can use 11gR2, 12c, 18c, 19c… Each year, you pay support fees: these fees give you access to My Oracle Support, for downloading patches or opening a Service Request in case of problem. But you are supposed to run recent version of the database with this premier support. For example, as of the 29th of November 2019, the versions supported with premier support are 22.214.171.124, 18c and 19c. If you’re using older versions, like 126.96.36.199 or 188.8.131.52, you should pay additional fees for extended support. Extended support is not something you have to subscribe indefinitely, as the purpose is only to keep your database supported before you migrate to a newer version and return to premier support.
So, keeping older versions will cost you more, and in-time migration will keep your support fees as low as possible.
For sure, migrating to 19c also comes at a cost, but we’re now quite aware of the importance of migrating software and stay up to date for a lot of reasons.
Motivate your software vendor or your development team to validate and support 19c. The amount of work for supporting 19c against 18c or 12c is quite the same. All these versions being actually 12c. The behaviour of the database will be the same for most of us. Avoid migrating to 184.108.40.206 or 18c as you’ll have to migrate again in 1 year. Keep your 11gR2 and/or 12cR1 and take extended support for one year while preparing the migration to 19c if you’re not yet ready. 20c will be a kind of very first release 1: you probably won’t migrate to this version if you mostly consider stability and reliability for your databases.