[debian-mysql] Redesigning the /var/lib/mysql/*.flag thing

[Otto Kekäläinen]

Hello!

2015-10-05 14:26 GMT+02:00 Robie Basak <robie.basak at canonical.com>:
> If were to implement my proposal, then the debconf option wouldn't a
> simple yes/no any more. As an example, if the user had MySQL 5.6 and
> were switching to MariaDB 10.0, we could prompt with multiple choices
> (we can work out the exact text and UX flow later):
>
> 1) Move the existing MySQL 5.6 database to MariaDB 10.0 and crossgrade
> it (irreversible).
>
> 2) Copy the existing MySQL 5.6 database to MariaDB 10.0 and crossgrade
> it (reversible in that the user could go back to MySQL 5.6 and the
> database would just go back in time).
>
> 3) Start a fresh MariaDB 10.0 database without impacting the MySQL 5.6
> database at all.
>
> From a disk space perspective, only option 2 really requires much space,
> and it should be relatively easy to warn the user or not present the
> option at all if it looks like it is unlikely to succeed.
>
> I think this eliminates potential for a dpkg abort and broken state,
> since not proceeding no longer needs to be an option. The user can
> always just choose option 3 instead, which will always be safe.


Ok, this would be good.

Two options could be enough:
1) move database, potentially not possible to migrate back
2) copy database, keeps ability to downgrade (if enough disk space)

This should be done in a context where the options apply for both
mysql/mariadb-changes, and also for users going back and forth between
different versions of the same mysql variant.


Are you planning to implement this yourself or should we have a sprint
and do it together? Are you planning to visit some FOSS conference
were we might both attend and sit down to do this?


- Otto

PS. Greetings from Amsterdam! Here is now the MariaDB dev meetup with
~60 people signed up and I think that most even also showed up.
Exiting things going on with the new plugins and Galera and others.