Re: creating CHECK constraints as NOT VALID

On 11 June 2011 14:32, Dean Rasheed <dean.a.rasheed@gmail.com> wrote:
> On 1 June 2011 23:47, Alvaro Herrera <alvherre@commandprompt.com> wrote:
>>
>> Here's a complete patch with all this stuff, plus doc additions and
>> simple regression tests for the new ALTER DOMAIN commands.
>>
>>    Enable CHECK constraints to be declared NOT VALID
>>
>>    This means that they can initially be added to a large existing table
>>    without checking its initial contents, but new tuples must comply to
>>    them; a separate pass invoked by ALTER TABLE / VALIDATE can verify
>>    existing data and ensure it complies with the constraint, at which point
>>    it is marked validated and becomes a normal part of the table ecosystem.
>>
>
> I think that you also need to update the constraint exclusion code
> (get_relation_constraints() or nearby), otherwise the planner might
> exclude a relation on the basis of a CHECK constraint that is not
> currently VALID.

Do the standards explicitly stipulate an expected behaviour for this?
And does such a problem affect the invalid foreign key change too?

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