Re: Add pg_stat_kind_info system view

Hi,

On Wed, Jul 01, 2026 at 10:35:33AM +0900, Michael Paquier wrote:
> On Tue, Jun 30, 2026 at 05:36:57PM -0500, Sami Imseih wrote:
> > + <structfield>count</structfield> <type>bigint</type>
> > + </para>
> > + <para>
> > + Number of tracked entries for this kind. For fixed-amount
> > kinds, this is
> > + always 1. For variable-numbered kinds, this is the number of objects
> > + currently tracked. <literal>NULL</literal> if the kind does not track
> > + entry counts.
> > + </para>
> > + </entry>
> >
> > I think this should be 0 for all kinds by default. Only ever > 0 for
> > variable-numbered
> > kinds with entry tracking enabled. No NULLs. The fields should be called
> > "entry_count" instead of "count". We should update the documentation to
> > reflect that as well. That seems easier to query than having mixed NULLs and
> > numbers.
>
> IMO, in this case, NULL should be a synonym of "I don't know", which
> is what entry_count set to false means. 0 means "I know, there is no
> data". I'd be OK with dropping the part about fixed-sized stats where
> we enforce 1, and use NULL instead, though.

+1, that's also my opinion [1].

[1]: https://postgr.es/m/ajtroNXfBS/ldtNZ%40bdtpg

Regards,

--
Bertrand Drouvot
PostgreSQL Contributors Team
RDS Open Source Databases
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