Re: Passing initially_valid values instead of !skip_validation to StoreRelCheck() in AddRelationNewConstraints()

On 2015/12/09 11:19, Amit Langote wrote:
> On 2015/12/09 5:50, Robert Haas wrote:
>> I suspect this is an oversight.  We allowed FOREIGN KEY constraints to
>> be not valid in 722bf7017bbe796decc79c1fde03e7a83dae9ada by Simon
>> Riggs, but didn't add allow it for CHECK constraints until Alvaro's
>> commit of 897795240cfaaed724af2f53ed2c50c9862f951f a few months later.
>> My guess is that there's no reason for these not to behave in the same
>> way, but they don't.  Amul's proposed one-liner might be one part of
>> actually fixing that, but it wouldn't be enough by itself: you'd also
>> need to teach transformCreateStmt to set the initially_valid flag to
>> true, maybe by adding a new function transformCheckConstraints or so.
>
> So, any NOT VALID specification for a FK constraint is effectively
> overridden in transformFKConstraints() at table creation time but the same
> doesn't happen for CHECK constraints. I agree that that could be fixed,
> then as you say, Amul's one-liner would make sense.

So, how about attached?

I think it may be enough to flip initially_valid to true in
transformTableConstraint() when in a CREATE TABLE context.

Regarding Amul's proposed change, there arises one minor inconsistency.
StoreRelCheck() is called in two places - AddRelationNewConstraints(),
where we can safely change from passing the value of !skip_validation to
that of initially_valid and StoreConstraints(), where we cannot because
CookedConstraint is used which doesn't have the initially_valid field.
Nevertheless, attached patch includes the former.

Thoughts?

Thanks,
Amit