F18 => F19 update adventures

[Adam Williamson]

On Tue, 2013-06-11 at 07:47 +0000, "Jóhann B. Guðmundsson" wrote:
> On 06/11/2013 06:38 AM, James Hogarth wrote:
> 
> > 
> > >
> > > What do administrators have to do to prevent being migrated from
> > mysql to mariadb on upgrades?
> > >
> > 
> > If you would prefer to use community-mysql rather than follow onto
> > MariaDB I suspect the safest thing would be take a backup (you do
> > that anyway right?) and just doing this from the filesystem is
> > probably the simplest way. 
> > 
> > Then use a supported method to upgrade to F19 ... Either remove
> > mysql before this or remove mariadb after this.
> > 
> 
> For the first we should not be migrating users on upgrades to another
> DB solution regardless if it's an fork or not of the already installed
> DB and we continue to ship it, secondly if we *must* do that ( which
> is it is not in this case since we are continuing to package and ship
> mysql ) we should have an opt out way for administrators to do so at
> upgrade time instead of having them to backtrack all the migration
> steps and revert them followed by them finally having to remove
> mariadb in this case an simply big fat warning presented at the end
> user during the upgrade phaze which offers him to opt out migration
> and continue to use MySQL... 

It's easy to say 'should' this and 'should' that and 'should' the other,
but it's rather more difficult to _do_ it. RPM fundamentally just
doesn't really give you the option of expressing the policy you suggest:
we can't have mariadb obsolete mysql but also have some kind of get-out
clause so people can override the obsolete and instead get
community-mysql. At least, that's my understanding of how the mechanisms
in question work. It just doesn't seem to be a thing that's possible.

I think the best thing that would be possible would be to install
community-mysql manually before triggering the rest of the upgrade, but
dependencies might become an issue. I suppose we could provide a
community-mysql package in F18 so people could switch to it before doing
the upgrade, but its presence might confuse people who didn't understand
the trick we were attempting.
-- 
Adam Williamson
Fedora QA Community Monkey
IRC: adamw | Twitter: AdamW_Fedora | identi.ca: adamwfedora
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