Re: Pg_upgrade and collation

Bruce Momjian wrote:
> 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.

By this argument, the proposed patch seems pointless to me.

> The larger issue of moving clusters is a separate issue that needs
> documentation somewhere else.

Sure.

--
Álvaro Herrera                http://www.2ndQuadrant.com/
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