MySQL 9.1 Release Notes
Notes
Make sure you understand the MySQL release model for MySQL for MySQL long long-term support (LTS) and Innovation versions before proceeding with a downgrade.
We recommend checking upgrade compatibility with MySQL Shell's Upgrade Checker Utility before performing an upgrade.
A replication topology is upgraded by following the rolling upgrade scheme described at Section 19.5.3, “Upgrading or Downgrading a Replication Topology”, which uses one of the supported single-server methods for each individual server upgrade.
Monthly Rapid Updates (MRUs) and hot fixes also count as releases in this documentation.
Table 3.1 Upgrade Paths for MySQL Server
| Upgrade Path | Path Examples | Supported Upgrade Methods |
|---|---|---|
| Within an LTS or Bugfix series | 8.0.37 to 8.0.41 or 8.4.0 to 8.4.4 | In-place upgrade, logical dump and load, replication, and MySQL Clone |
| From an LTS or Bugfix series to the next LTS series | 8.0.37 to 8.4.x LTS | In-place upgrade, logical dump and load, and replication |
| From an LTS or Bugfix release to an Innovation release before the next LTS series | 8.0.34 to 8.3.0 or 8.4.0 to 9.1.0 | In-place upgrade, logical dump and load, and replication |
| From an Innovation series to the next LTS series | 8.3.0 to 8.4 LTS | In-place upgrade, logical dump and load, and replication |
| From an Innovation series to an Innovation release after the next LTS series | Not allowed, two steps are required: 8.3.0 to 8.4 LTS, and 8.4 LTS to 9.x Innovation | In-place upgrade, logical dump and load, and replication |
| From within an Innovation series | 8.1.0 to 8.3.0 | In-place upgrade, logical dump and load, and replication |
| From MySQL 5.7 to an LTS or Innovation release | MySQL 5.7 to 8.4 | A bugfix or LTS series cannot be skipped, so in this example first upgrade MySQL 5.7 to MySQL 8.0, and then upgrade MySQL 8.0 to MySQL 8.4. |