In the MySQL team, we have always had a requirement to support upgrades from one major version. For example:
- Upgrading from MySQL 5.5 to 5.6 is supported.
- Upgrading from MySQL 5.1 to 5.6 is not supported.
Downgrades are also supported for one major version. For example, if a user upgrades to 5.6 but discovers that it is not working as expected, they have the safety knowing that there is a way to step back to MySQL 5.5. This may come with some limits; for example when new features (such as new row formats or page checksums) are enabled, this may no longer be possible.
Today I wanted to discuss a current non-requirement. We do not support skipping major versions, such as upgrading from MySQL 5.1 to 5.6. Justin however makes the …[Read more]