[development] Incremental upgrades

[Neil Drumm]

On 7/27/07, Gabor Hojtsy <gabor at hojtsy.hu> wrote:
> Cog Rusty wrote:
> >> Well, update.php does not include older updates, so if one has an older
> >> 4.x site (let's say 4.5 or 4.4), he cannot upgrade directly, but first
> >> go to an intermediate version. I have not looked into it, but update.php
> >> might have problems, or would not inform the user, if he has such an old
> >> system that has no updates in the actual update.php/update.inc/*.install
> >> files code.
> >
> > The question remains, because how would it help to upgrade such an old
> > version first to 5.1 and not to 5.2?
> >
> > An advice which seemed safe so far was
> > (a) never skip major versions
> > (b) when stepping to the next major version use its latest minor
> > version, assuming that it would be more "bug-fixed"
>
> Absolutely agreed.

Theoretically, 4.0 straight up to 5.2 in one go should work. All the
upgrade scripts are in 5.2. However, changes do sometimes break old
updates. Updates aren't especially tested for this since most core
developers go straight out of the older versions and stop giving much
thought to them.

-- 
Neil Drumm
http://delocalizedham.com