On Wednesday, August 14, 2024, PG Bug reporting form <
noreply@postgresql.org> wrote:
The following bug has been logged on the website:
Bug reference: 18583
Logged by: Robert Greig
Email address: robert.j.greig@gmail.com
PostgreSQL version: 16.4
Operating system: Windows
Description:
create type test_simple_type as (
f1 varchar(20),
f2 int
);
where val is not null;
It is not obvious to me why it is not working but I believe this is a defect
and I can't find a workaround.
The “workaround” is to write that test: not (val is null)
The meaning of is not null for a composite is non-intuitive and usually not what you want - i.e., true only if all fields are also non-null.
The docs do cover this, and there is a pending patch to further expand on how null values are handled in various places in PostgreSQL.
David J.
