Re: BUG #14701: pg_dump fails to dump pg_catalog schema

On 12 June 2017 at 12:18, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Peter Eisentraut <peter(dot)eisentraut(at)2ndquadrant(dot)com> writes:
>> On 6/11/17 20:19, Tom Lane wrote:
>>> Alternatively, I think that CREATE COLLATION
>>> ought to grow the ability to accept "provider = default" and pg_dump
>>> should use that.
>
>> We could probably do that at least in pg_dump. What are the
>> expectations for pg_catalog schema dumps? Are they supposed to be
>> restorable?
>
> Hmm, well, actually not --- it certainly wouldn't make any sense to
> try to create pg_class again, for instance. You could imagine changing
> the schema name and creating a clone of all the objects, but that
> only works for objects with schema-qualified names. So mostly this
> is only useful for documentation, which I think is Neil's use-case
> anyway.

Yes that's what I was using it for. I thought it worth reporting just
in case it was a symptom of something bigger. Hopefully it's just for
my uncommon case :)

>
> That leads to the idea that it would be okay to let pg_dump print
> "provider = default" but *not* let CREATE COLLATION accept that.
> If we did that and also disallowed cloning the default collation,
> then we'd have the property that only the original default collation
> has provider 'd', and the existing code would continue to work.
>
> regards, tom lane