Except that this change means that the behaviour of nulls is not weird anymore!
That sql null is valid doesn’t make its behaviour of not being equal to itself any less weird, because it works that way essentially nowhere else, and thus is highly unintuitive to developers who don’t live and breathe sql.
The closest thing in most langages is nan and developers also find nan weird.
I'd argue the closest thing in most languages is the null propagation operator (usually using a ? symbol) that at least JavaScript and C# have.
YMMV, but personally the unique index behaviour was the main thing I found weird about NULLs. So now that I can turn that off I'm pretty happy with them.
In what sense? null-coalescing operators don’t change how nulls behave or relate to one another, they only provide convenience operators for conditioning operation upon them, like sql’s COALESCE.
I find it quite useful to know when something is null though I have a hard time explaining it.
> It's perfectly valid.
:o You'll get jumped on, saying this to a forum of software people. Lots of things that are valid are also weird.
[0] https://www.postgresql.org/docs/14/functions-logical.html
Say you have a unique constraint on two columns (column_a, column_b). column_a is not nullable, column_b IS nullable. Obviously these values are unique:
(1, 2) (1, 3) (2, 2)
But these values ARE ALSO UNIQUE:
(1, NULL) (1, NULL)
It is obvious in hindsight (NULL isn't equal to NULL), but can be quite a surprise.
...
Oh wait, postgres 15 deals with just this situation. Huh.