Re: Pg_upgrade and collation

On Fri, Jun 17, 2016 at 06:01:59PM -0400, Bruce Momjian wrote:
> On Fri, Jun 17, 2016 at 05:51:54PM -0400, Alvaro Herrera wrote:
> > Bruce Momjian wrote:
> > > The attached patch documents that pg_upgrade requires old/new servers to
> > > use compatibile collation library versions as well.
> >
> > I think this is way too thin to be helpful:
>
> Well, this is a much larger issue than pg_upgrade, e.g. moving a data
> directory from one cluster to another with a different collation library
> version could also cause problems, and I don't know that is documented
> at all.
>
> If we want to go larger, we have to do this in a more central location.

Frankly, pg_upgrade is, by definition, upgrading on the same server, so
I don't even see how they could have mismatched collation library
versions, but it seemed good to document it.  The larger issue of moving
clusters is a separate issue that needs documentation somewhere else.

--
  Bruce Momjian  <bruce@momjian.us>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

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