jian he <jian(dot)universality(at)gmail(dot)com> writes:
> then I think I found a bug for applying fast default over domain with
> default value.
Yeah, that's definitely a bug: it worked correctly in versions
before we invented the attmissingval mechanism.
> column b type is domain int_domain3, which has a constraint.
> As a result, adding column b triggers a table rewrite, ensuring the
> domain default value is successfully applied.
I do not believe that case should require a table rewrite.
Both the default and the check constraint are immutable,
so we ought to be able to apply the check once and then
use the default as the attmissingval.
> Attach a patch to fix this issue by cause it to table rewrite.
I see no attached patch, but in any case forcing a table rewrite
seems like the wrong direction...
regards, tom lane