> And? Oracle and MySql doesnt have it but can downgrade right out the box.
> Quick and easy.
No it is not for mysql.
http://dev.mysql.com/doc/refman/5.7/en/downgrading.html
"In-place Downgrade: Involves shutting down the new MySQL version,
replacing the new MySQL binaries or packages with the old ones, and
restarting the old MySQL version on the existing data directory.
In-place downgrades are supported for downgrades between GA versions
within the same release series. For example, in-place downgrades are
supported for downgrades from 5.7.10 to 5.7.9.
The above is easy and same as PG if you are going from 9.5.2 to 9.5.1.
"
Now let us take about major downgrade.
Downgrading one release level is supported using the logical downgrade
method. For example, downgrading from 5.7 to 5.6 is supported. Logical
Downgrade: Involves using mysqldump to dump all tables from the new
MySQL version, and then loading the dump file into the old MySQL
version. Logical downgrades are supported for downgrades between GA
versions within the same release series and for downgrades between
release levels. For example, logical downgrades are supported for
downgrades from 5.7.10 to 5.7.9 and for downgrades from 5.7 to 5.6.
Only a fool will consider this as simple. And BTW all products support
methods similar to mysqldump. What we are looking at, is an in-place
downgrade after a major version upgrade and that looks to be almost
non-existent.