I suppose that DEFAULT syntax should be used to set setting to its default value. Eg.
set_config( 'my.option', DEFAULT, false )
This is clear what should happen here. Also this syntax will correspond to other places, eg. INSERT INTO xx (name) VALUES (DEFAULT).
Using NULL to set reset the value to the default is very very confusing.
set_config( 'my.option', NULL, false )
Expected: this call should make option unrecognizable again.
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Кому: David G. Johnston (david.g.johns...@gmail.com), pgsql-docs@lists.postgresql.org (pgsql-docs@lists.postgresql.org);
Тема: Unexpected behaviour: it was documented to return the same value;
13.07.2025, 16:34, "KES" <kes-...@yandex.ru>:
I would prefer to remove the option from the configuration list instead of having it reset to empty string.Eg. set_config( 'my.option', NULL, false )Having it to return the empty string cause differences in the behaviour when parameter is not recognized at all and when it setup to default.How to make it "unrecognizable" again using set_config/RESET?The exact problem I am trying to resolve was asked here: https://stackoverflow.com/q/50923911/4632019----------------Кому: kes-...@yandex.ru (kes-...@yandex.ru), pgsql-docs@lists.postgresql.org (pgsql-docs@lists.postgresql.org);Тема: Unexpected behaviour: it was documented to return the same value;07.07.2025, 17:40, "David G. Johnston" <david.g.johns...@gmail.com>:On Mon, Jul 7, 2025 at 6:51 AM David G. Johnston <david.g.johns...@gmail.com> wrote:On Saturday, July 5, 2025, PG Doc comments form <nore...@postgresql.org> wrote:The following documentation comment has been logged on the website:
Page: https://www.postgresql.org/docs/17/functions-admin.html
Description:Yeah, this clarification just wasn't back-patched."set_config accepts the NULL value for new_value, but as settings cannot be null, it is interpreted as a request to reset the setting to its default value."David J.
