Re: BUG #16945: where value in (null) set results inconsistent

On Mon, Mar 29, 2021 at 8:41 AM PG Bug reporting form <noreply@postgresql.org> wrote:

...

Pursuant to a fix in Hibernate, that uses "where value in (null)" as a
workaround for several DB's not handling "where value in ()":
https://hibernate.atlassian.net/browse/HHH-8091

Consider this inconsistency:

... 

The expression `id in (null)`  is equivalent to `id = null` which is always null (or more accurately Uknown) and where unknown will have the same result as where false.

Workarounds:

where id in (select null::int where false)

where id not in (select null::int where false)

or avoiding the cast:

where id in (select id from project_type_variants where false)

where id not in (select id from project_type_variants where false)