Horton

Re: Some tests for TOAST, STORAGE MAIN/EXTENDED

Michael Paquier <michael@paquier.xyz>

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From: Michael Paquier <michael@paquier.xyz>
To: Nikhil Kumar Veldanda <veldanda.nikhilkumar17@gmail.com>
Cc: Postgres hackers <pgsql-hackers@lists.postgresql.org>
Date: 2026-01-25T00:46:51Z
Lists: pgsql-hackers 
On Fri, Jan 23, 2026 at 12:25:33AM -0800, Nikhil Kumar Veldanda wrote:
> The `SELECT count(*) FROM :reltoastname` assertion is a bit brittle
> for `STORAGE EXTENDED`: depending on the toast compression method /
> effectiveness, the value may end up as >1 chunk, which would flip the
> expected count(*) = 1. Prefer SELECT count(DISTINCT chunk_id) FROM
> :reltoastname (or WHERE chunk_seq = 0) and adjust expected.

Yeah, this suggestion sounds sensible and that would still notice what
I was able to break.

> pg_column_compression() expects pglz, but default_toast_compression
> isn’t pinned here. Suggest SET default_toast_compression = 'pglz';
> near this block; otherwise this can fail on builds with a different
> default.

Agreed, let's do that as well.
--
Michael

Commits

  1. Add more tests with clause STORAGE on table and TOAST interactions