[development] Incremental upgrades

[Cog Rusty]

On 7/27/07, Gabor Hojtsy <gabor at hojtsy.hu> wrote:
> Earnie Boyd wrote:
> >> What is the purpose of this? (Not recommending to go straight to 5.1
> >> when it was released, but recommending it now that 5.2 has been
> >> released.) Is it a safety valve in case something upgrade-related has
> >> been overlooked in the new release?
> >>
> >> Or does it mean that one has to follow the chain and trace back all
> >> the minor releases one by one?
> >
> > Good questions, I would also like to ask why upgrade.php should not
> > handle a straight 4.x to 5.2?  Isn't it designed to prevent the need to
> > do incremental upgrades so that all of the needed upgrades are self
> > contained?
>
> 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"

People seem to have been doing that successfully. So, it surprised me
to see a suggestion to go first to the second-newest minor version
every time..


> Previously the numbers were linear, so if you had a system updated to
> version 12, and you could only run updates from 17 through 32, then the
> missing 13-16 updates would result in a corrupted system. Now the
> numbers are not linear, there are version jumps, so telling if you miss
> updates is harder. Who knows if there were 600x updates after the 6008
> update you have done last on your site or not?
>
> That said, it would be great to test and document from what version can
> people upgrade to a particular Drupal version, and and document that
> instead of suggesting intermediary updates for all cases.
>
> Gabor
>