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Introducing MySQL Innovation and Long-Term Support (LTS) versions (oracle.com)

Introducing MySQL Innovation and Long-Term Support (LTS) versions

July 18, 2023 | 12 minute read

Kenny Gryp

MySQL Product Management Director

Airton Lastori

MySQL Product Manager

 

At Oracle, we constantly look for ways to improve our products to better fit your needs. We are excited to introduce MySQL Innovation and Long-Term Supported releases, which is an important improvement in the MySQL versioning model.

The patch releases of MySQL 5.7 and previous releases were focused on bugfix and security patches. That changed in MySQL 8.0 with the continuous delivery model in that patch releases also contained new features. That allowed MySQL to release new features to users more frequently rather than only being able to release features every few years. However, we understand that this approach can cause challenges for projects and applications that require only critical patches with less frequent behavior changes. We listened to your feedback and observed industry trends, and we are now transitioning to a versioning model where you can choose between Innovation and Long-Term Support (LTS) releases.

Both Innovation and LTS are production-grade quality. If you desire access to the latest features and improvements and enjoy staying on top of the latest technologies, the MySQL Innovation releases might be the best fit for you. These releases are ideal for developers and DBAs working in fast-paced development environments with high levels of automated tests and modern continuous integration techniques for faster upgrade cycles. On the other hand, if your environment requires established behavior, then the LTS releases are the way to go. These releases contain only necessary fixes, so they reduce the risks associated with changes in the database software's behavior.

With the new MySQL versioning model, you have the flexibility to select the option that suits your specific application and environment needs. Our goal is to ensure that you have an exceptional user experience with both Innovation and LTS releases. You can discover additional information about the new versioning model and the transition process below.

Transitioning into Innovation and LTS releases

We're transitioning to the new MySQL versioning model with our upcoming versions. MySQL database version 8.1.0 will be our first Innovation release, and 8.0.34+ will transition to only bug fixes until 8.0 End-Of-Life (EOL) scheduled for April-2026. Approximately one year from now, MySQL version 8.x will eventually become LTS which will provide ample time for users to migrate from 8.0.x to the 8.x LTS version.

In practice, in this transition period, if you want the latest features, improvements, and all bug fixes for your MySQL databases, use the Innovation release track (eg., 8.1.x, 8.2.x, 8.3.x, etc.). If you need only bug fixes for your MySQL database, use 8.0.x releases (eg., 8.0.35, 8.0.36, 8.0.37, etc.). In both cases, you should plan to update your MySQL databases quarterly accordingly to Oracle Critical Patch Updates (CPU) calendar. When 8.x becomes LTS, you can plan, test, and migrate from the 8.0.x bug fix track to the LTS release track (ex., from 8.0.37 to 8.4.1).

MySQL HeatWave Database Service

MySQL HeatWave database service is fully managed, developed, and supported by Oracle's MySQL team. We provide the latest improvements and security patches through up-to-date MySQL database versions. MySQL HeatWave customers have access to bug fixes from day-1 and the latest features, including OLTP, OLAP, machine learning, and Lakehouse.

MySQL HeatWave users now have the option to select from Innovation releases, beginning with 8.1.0, and Bug Fix releases, beginning with 8.0.34. The service gives flexibility in choosing the MySQL version per DB System, enabling users to mix and match versions based on application requirements. Those using 8.1+ Innovation releases can take full advantage of the service's potential, gaining access to the latest features and bug fixes. Alternatively, those who only require critical bug fixes and do not need the latest features can opt for 8.0.x releases for their MySQL DB Systems.

MySQL Portfolio & Support Lifecycle

LTS Releases will follow the Oracle Lifetime Support Policy, which includes 5 years of premier and 3 years of extended support. Innovation releases will be supported until the next major & minor release.

Most products in MySQL's portfolio will have Innovation and LTS versions:

• MySQL Server, MySQL Shell, MySQL Router, MySQL NDB Cluster will have Innovation and LTS releases.
• MySQL Operator for Kubernetes, with InnoDB ReplicaSet, Cluster and ClusterSet will have Innovation and LTS releases.
• MySQL Connectors will use the latest version used, but will be considered Generally Available and will remain compatible with all supported MySQL Server versions.
• MySQL Workbench will remain on 8.0.x and is Generally Available and will remain compatible with all supported MySQL Server versions.

MySQL Versions Release Cadence

• MySQL 8.0.34+ will become bugfix only release (red)
• Innovation releases (grey) will likely happen quarterly
• About every 2 years a new Long Term Support version will be released (blue). An exception is the 8.x LTS release which will happen well before EOL of 8.0

For the next few years, the MySQL versioning will look similar to the example diagram as shown:

Note that this is an example, there is no commitment that the version numbering will be exactly as presented.

Innovation Releases

Innovation releases are similar to MySQL 8.0 continuous development model (< 8.0.34) and include bugfixes, security patches, and new features.

Support for Innovation releases is limited until the next minor release (Innovation or LTS). The current cadence goal is to have an Innovation release every quarter, incrementing the minor version number (eg. 8.2, 8.3, etc.). Patch releases within Innovation releases are possible but are less likely to happen.

Innovation releases will also be Generally Available and are recommended to be used in production environments. Bugfixes and Security patches will generally be included in the next Innovation or LTS release and not as part of a patch release within that Innovation release. When using Innovation releases, it is necessary to upgrade to the latest innovation releases regularly to keep up with the latest bugfixes and security patches.

In addition to bugfixes, security patches and new features, Innovation releases will introduce new deprecations, removal of features, and even behavior changes. To reduce the risk and complexity of upgrading when such changes are introduced, policies and best practices on when and how will be put in place.

Deprecation & Removal of Features

In previous releases of MySQL, deprecations in one release (e.g., 5.7) meant that the feature could be removed in the next major/minor release (e.g., 8.0). With the introduction of Innovation releases, there will be a lot more major/minor versions, and as a result of that, when deprecations and removals can happen will change.

When a feature or behavior is deprecated in a release (e.g., 9.2 Innovation), the feature cannot be removed for at least one year (until 9.6 Innovation). This is to give users time to modify database deployments when they are running Innovation releases.

Note that there are no removals within an LTS release. Features can be removed (& added) only in the first LTS release (e.g., 8.4.0 LTS) but not later.

As we transition into the new model and move towards the first 8.x LTS release, expect an increase in deprecations and removals.

Behavior Changes

Apart from new features in Innovation releases, behavior changes are also to be expected as code gets refactored or when MySQL is modified to behave more in line with SQL Standards (this will not happen within an LTS release).

Behavior changes can have a big impact, especially when dealing with anything application related, such as SQL Syntax, new reserved words, query execution, or even query performance. Behavior changes might require application changes which can be a considerable effort for our users to migrate.

In addition to documenting each behavior change, it is important that our users are provided with the necessary tools and configuration settings to make it possible and easy to upgrade and downgrade between versions. Different approaches will be used depending on the type of behavior change. More details will come as we introduce such changes.

Long Term Supported Releases

About every 2 years, a minor version will be designated as Long Term Supported release. This version will have a 5 year premier and 3 year extended support, the same as the previously supported releases. This is similar to MySQL 5.7 and previous releases.

The LTS will also be the last version of the major release. The next (Innovation) release will increase it's major version. For example if MySQL 8.4.0 is the 8.x LTS release, then MySQL 9.0 will be the next Innovation release.

Upgrading & Downgrading

With the increased cadence of major & minor Innovation releases and LTS releases every 2 years, users will have more supported versions to choose from. Being an adopter of the Innovation series will require frequent updates to follow the bugfixes and security patches and that requires upgrade and downgrade policies.

Let's have a more in-depth look into the various upgrade & downgrade scenarios that will be supported.

Upgrading & Downgrading within an LTS release

Within an LTS release, functionality remains the same and data format does not change.

Therefore:

• In-place upgrades and downgrades will be possible. This is an improvement compared to MySQL 8.0.x releases (< 8.0.34) where downgrades were not possible and upgrade by skipping versions were not recommended.
• InnoDB CLONE will be supported within an LTS release, both for upgrading and downgrading.

Some more work is needed to fully transition to this and will come in a release after 8.0.34.

Upgrading & Downgrading from one LTS to another LTS

• It will be possible to migrate from one LTS release to the next LTS release without having to perform several intermediate steps of upgrading Innovation releases.
• Upgrading will be possible through in-place upgrades, MySQL Shell Dump & Load and MySQL asynchronous replication.
• Downgrades will be possible through MySQL Shell Dump & Load and MySQL replication for the sole purpose of rolling back an in-progress upgrade, more below.

Upgrading & Downgrading between Innovation releases

• In-place upgrades from one Innovation or LTS release to a future Innovation release will be supported, up until the next LTS release. replication and dump & load will also work.
• Downgrading will require a logical dump & load. This is similar to MySQL 8.0.x (< 8.0.34).

Upgrading & Downgrading with MySQL asynchronous replication

Upgrades on business critical environments are often done using MySQL asynchronous replication, where a new version environment is setup as replica of the current version. This allows for a near zero downtime upgrade.

It will be possible to replicate from an LTS or Innovation release to

• the next LTS release
• any future Innovation release up until the next LTS release (LTS 8.4 → LTS 9.7, but not LTS 8.4 → LTS 10.7)

In case any problems happen after promoting the new version, support to replicate back to the previous version is important. Therefore MySQL asynchronous replication will be able to replicate to previous versions. This support would be for rollback purposes only, where new functionality is not yet used, and shouldn't be considered part of a regular continuous production deployment.

Upgrade & Downgrade Support Matrix

Here's an overview of the various supported methods of upgrading and downgrading

Upgrade

	In-Place	CLONE	Async replication	Dump/Load
LTS 8.4 → LTS 9.7	✓	✗	✓	✓
LTS 8.4.11 → LTS 8.4.20	✓	✓	✓	✓
Innovation 8.1 → 8.2	✓	✗	✓	✓
Innovation 8.1 → 8.3	✓	✗	✓	✓
Innovation 9.1 → LTS 9.7	✓	✗	✓	✓
LTS 8.4 →  LTS 10.7	✗	✗	✗	✗

Downgrade

	In-Place	CLONE	Async replication	Dump/Load
LTS 8.4.20 → 8.4.11	✓	✓	✓	✓
LTS 9.7 → LTS 8.4	✗	✗	✓✮	✓✮
LTS 9.7 → Innovation 9.6	✗	✗	✓✮	✓✮
LTS 9.7 → Innovation 9.5	✗	✗	✓✮	✓✮

(✮) indicates support is limited for rollback purposes only.

Conclusion

As we transition to this new model, we welcome you to engage with our Community channel and our Support team.

You can download the latest MySQL releases at mysql.com/downloads or use Oracle Software Delivery Cloud on http://edelivery.oracle.com/ to download MySQL Enterprise binaries.

For detailed information about each release, including new features, improvements, bug fixes, and possible breaking changes, check the MySQL Release Notes.

In addition to 8.0, MySQL HeatWave database service now provides the latest MySQL 8.1 Innovation release. This includes the latest features, including OLTP, OLAP, machine learning, and Lakehouse. For a free trial account, visit oracle.com/mysql/free.

We're thrilled about the opportunities this new versioning model will bring and eagerly await your feedback. Together, we can continue to make MySQL even better.