Chapter 4 Downgrading MySQL

Notes

• Make sure you understand the MySQL release model for MySQL long-term support (LTS) and Innovation releases before proceeding with a downgrade.

• A replication topology is downgraded by following the rolling downgrade 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 downgrade.

• Monthly Rapid Updates (MRUs) and hot fixes also count as releases in this documentation.

Table 4.1 Downgrade Paths for MySQL Server

Downgrade Path	Path Examples	Supported Downgrade Methods	Notes
Within an LTS series	8.4.y LTS to 8.4.x LTS	In-place, logical dump and load, MySQL Clone, or by using replication
From an LTS or Bugfix series to the previous LTS or Bugfix series	8.4.x LTS to 8.0.y	Logical dump and load or by using replication	Only supported for rollback purposes (that is, if no new server functionality has been applied to the data)
From an LTS or Bugfix series to an Innovation series after the previous LTS series	8.4.x LTS to 8.3.0 Innovation	Logical dump and load or by using replication	Only supported for rollback purposes (that is, if no new server functionality has been applied to the data)
From within an Innovation series	9.1 to 9.0	Logical dump and load or by using replication	Only supported for rollback purposes (that is, if no new server functionality has been applied to the data)

Downgrading to MySQL 5.7 or earlier is not supported.