Horton

Re: misleading error message in ProcessUtilitySlow T_CreateStatsStmt

Tom Lane <tgl@sss.pgh.pa.us>

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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Álvaro Herrera <alvherre@kurilemu.de>
Cc: Kirill Reshke <reshkekirill@gmail.com>, jian he <jian.universality@gmail.com>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2025-08-22T14:37:24Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. CREATE STATISTICS: improve misleading error message

  2. Glossary: improve definition of "relation"

  3. Extended statistics on expressions

=?utf-8?Q?=C3=81lvaro?= Herrera <alvherre@kurilemu.de> writes:
> I'm not sure.  See the definition of relation in the glossary:
> https://www.postgresql.org/docs/18/glossary.html#GLOSSARY-RELATION

>   The generic term for all objects in a database that have a name and a
>   list of attributes defined in a specific order. Tables, sequences,
>   views, foreign tables, materialized views, composite types, and
>   indexes are all relations.

>   More generically, a relation is a set of tuples; for example, the
>   result of a query is also a relation.

>   In PostgreSQL, Class is an archaic synonym for relation.

> (I wonder why this says "generically" rather than "generally".  Is that
> word choice a mistake?)  Maybe in the "For example" clause we can also
> mention table functions.

Yeah, I think s/generically/generally/ would be an improvement.

I'm not certain, but I think that our use of "relation" to mean
"an object with a pg_class entry" is a Postgres-ism.  I do know
that the meaning of "a set of tuples" is widely used, as that's
where the term "relational database" comes from.  Maybe whoever
wrote this was trying to get at that point?  But this text is
hardly clear about that.

			regards, tom lane