Re: Clarification to pg_upgrade docs on reverting to old cluster

On 4/5/19 8:26 AM, Magnus Hagander wrote:
>
>
> On Thu, Apr 4, 2019 at 11:14 PM Daniel Gustafsson <daniel(at)yesql(dot)se
> <mailto:daniel(at)yesql(dot)se>> wrote:
>
> Reading the pg_upgrade reference page, I get the feeling that one of the
> bullets under "Reverting to old cluster" is a bit thin on detail to
> be helpful
> to newcomers:
>
>     "If you ran pg_upgrade with --link, the data files are shared
> between the
>     old and new cluster.  If you started the new cluster, the new
> server has
>     written to those shared files and it is unsafe to use the old
> cluster."
>
> This is perfectly correct, but it fails to provide information on
> what to do
> next in case reverting is in fact what the user wants.  The attached
> patch adds
> a short sentence saying the old cluster should be restored from
> backups at this
> point.
>
>
> Let's have two non-english natives discuss it :), but wouldn't it sound
> better with "in this case" than "at this point"? And as a really small
> nitpick, restore from backup, rather than backups?

I would go with:

"If you need to restore the old cluster, you will have to do so using
backups that you took prior to the upgrade."

Or if you want to be overly verbose:

"If you need to restore the old cluster, you will have to do so using
backups that you made prior to the upgrade as the --link does not create
a copy of the old cluster files."

Jonathan