Re: 'pg_global' cannot be used as default_tablespace.

On Wed, Nov 1, 2023 at 07:34:59PM -0400, Bruce Momjian wrote:
> On Wed, Nov 1, 2023 at 07:12:48PM -0400, Tom Lane wrote:
> > Bruce Momjian <bruce(at)momjian(dot)us> writes:
> > > On Wed, Nov 1, 2023 at 06:32:37PM -0400, Tom Lane wrote:
> > >> But it *is* permissible, unless we add code to reject it during
> > >> SET as Bruce mentioned. Which seems fairly pointless to me. It's not
> > >> like there is anything unclear about the CREATE TABLE error message.
> >
> > > Yeah, from the report I thought something bad happened if you tried to
> > > use it and that is why we had to document it. By documenting it we are
> > > just giving the user advice before they get the error. I wrote up this
> > > minimal patch which might have the right level of detail to avoid
> > > errors, if people think this is useful.
> >
> > I think this will lead to just as much confusion, because people
> > will read it and expect that SET will fail.
> >
> > If we need to document any more than we have now, we should point
> > out in the CREATE TABLE man page that you can't create a table in
> > the pg_global tablespace. That will cover both this case and the
> > case of trying to select pg_global explicitly in the CREATE.
> >
> > Another idea could be to adjust this bit in manage-ag.sgml:
> >
> > Two tablespaces are automatically created when the database cluster
> > is initialized. The
> > - <literal>pg_global</literal> tablespace is used for shared system catalogs. The
> > + <literal>pg_global</literal> tablespace is used for shared system catalogs,
> > + and cannot be used for user-defined tables. The
> > <literal>pg_default</literal> tablespace is the default tablespace of the
>
> I like the manage-ag.sgml change myself.

I found a cleaner improvement, attached.

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Bruce Momjian <bruce(at)momjian(dot)us> https://momjian.us
EDB https://enterprisedb.com

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