Re: not null constraints, again

Alvaro Herrera <alvherre@alvh.no-ip.org> 于2025年4月16日周三 19:24写道：

> Here's another version where I do skip searching for children twice, and
> rewrote the comments.
>
> I also noticed that in child tables we were only looking for
> pg_attribute.attnotnull, and not whether the constraints had been
> validated or made inheritable.  This seemed a wasted opportunity, so I
> refactored the code to instead examine the pg_constraint row and apply
> the same checks as for the constraint on the parent (namely, that it's
> valid and not NO INHERIT).  We already check for these things downstream
> (alter table phase 2, during AdjustNotNullInheritance), but only after
> potentially wasting more work, so it makes sense to do it here (alter
> table phase 1) given that it's very easy.  I added some tests for these
> things also, as those cases weren't covered.
>

if (conForm->contype != CONSTRAINT_NOTNULL)
    elog(ERROR, "constraint %u is not a not-null constraint", conForm->oid);

I feel that using conForm->conname is more friendly than oid for users.

Others look good for me.

-- 
Thanks,
Tender Wang