Re: Dead code with short varlenas in toast_save_datum()

Hi all,

On Sun, Aug 3, 2025 at 8:16 PM Michael Paquier <michael(at)paquier(dot)xyz> wrote:
> if (VARATT_IS_SHORT(dval))
> {
> data_p = VARDATA_SHORT(dval);
> data_todo = VARSIZE_SHORT(dval) - VARHDRSZ_SHORT;
> toast_pointer.va_rawsize = data_todo + VARHDRSZ; /* as if not short */
> toast_pointer.va_extinfo = data_todo;
> }
>
> Coverage link:
> https://coverage.postgresql.org/src/backend/access/common/toast_internals.c.gcov.html
>

This code path is currently not covered by tests. It can be exercised
with the following SQL pattern

CREATE TABLE temp_tbl (a text, b text);
ALTER TABLE temp_tbl SET (toast_tuple_target = 128);
ALTER TABLE temp_tbl ALTER COLUMN a SET STORAGE EXTERNAL;
ALTER TABLE temp_tbl ALTER COLUMN b SET STORAGE EXTERNAL;
INSERT INTO temp_tbl values(repeat('a', 4000), repeat('a', 120));

--
Nikhil Veldanda