> On 2 May 2026, at 00:41, Andres Freund <andres@anarazel.de> wrote:
>
> This is checking (as you noted) !VARATT_IS_EXTENDED, whereas the
> bt_normalize_tuple() code is checking !VARATT_IS_COMPRESSED.
>
> VARATT_IS_EXTENDED() will return true for short varlenas (because it's not a
> standard 4 byte uncompressed varlena), whereas VARATT_IS_COMPRESSED() will
> return false for a short varlena (since it's not compressed).
>
> I didn't find other instanes of similar code that uses !VARATT_IS_COMPRESSED.
As far as I understand
!VARATT_IS_COMPRESSED(DatumGetPointer(normalized[i])) && !VARATT_IS_SHORT(DatumGetPointer(normalized[i]))
is exactly
!VARATT_IS_EXTENDED(DatumGetPointer(untoasted_values[i]))
Which is what was proposed in v2 patch. But later was changed to !VARATT_IS_COMPRESSED().
As I understood it was done to further strengthen normalization.
So the intent might be that short varatts need normalization in some cases. But we have no tests that show such a case.
I tried to build a problematic storage alternation like [0], but everything works nicely.
So I propose something in a line with attached patch.
Best regards, Andrey Borodin.
[0] https://github.com/postgres/postgres/blob/master/contrib/amcheck/sql/check_btree.sql#L170-L172
