Re: Extended Statistics set/restore/clear functions.

Corey Huinker <corey.huinker@gmail.com>

From: Corey Huinker <corey.huinker@gmail.com>
To: Michael Paquier <michael@paquier.xyz>
Cc: jian he <jian.universality@gmail.com>, Tomas Vondra <tomas@vondra.me>, pgsql-hackers@lists.postgresql.org, tgl@sss.pgh.pa.us
Date: 2025-11-18T02:34:14Z
Lists: pgsql-hackers
On Mon, Nov 17, 2025 at 6:35 PM Michael Paquier <michael@paquier.xyz> wrote:

> On Mon, Nov 17, 2025 at 08:53:35PM +0800, jian he wrote:
> > segfault:
> > SELECT '[{"attributes" : [1,2,3,4,5,67,6,7,8], "ndistinct" :
> 4}]'::pg_ndistinct;
> >
> > because src/backend/statistics/mvdistinct.c line: 310, Assert
> > Assert((item->nattributes >= 2) && (item->nattributes <=
> STATS_MAX_DIMENSIONS));
>
> Ahah, good one here.  Perhaps we had better switch this assertion to
> become an elog() with the import functions in mind, as well.  It may
> be worth double-checking the other deserialization paths, as well.  We
> need to be super careful about this stuff for data imports.
>

Yeah, I liked that one too, and I can act on that while we're debating how
tightly to turn the screws on combinatorics.