Re: Bug in ALTER COLUMN SET DATA TYPE ?

On Mon, Nov 5, 2012 at 4:41 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:

>
>
> It's clear that we need to pass down the information that this action is
> coming from re-creation of a check constraint, but I think the above
> proposal for how to do it is pretty wrong-headed.

Yeah, I only meant that we need to teach ATExecAddConstraint that its being
called from the specific pass of ALTER TABLE and wanted to get agreement on
that. I hadn't thought about any particular implementation. So your
proposal below looks absolutely fine and clean.

>
> I'm inclined to think the cleanest solution is to add another value of
> enum AlterTableType, perhaps "AT_ReAddConstraint", to signal that we're
> executing a re-add; and then add another bool parameter to
> ATExecAddConstraint to tell the latter not to complain if child tables
> exist. This is more in line with pre-existing coding choices such as
> the use of AT_AddConstraintRecurse.
>

Please see attached patch which does what you suggested above. May be it
needs a little more commentary to record why we made this specific change.
Please let me know if you think so and want me to do that.

Thanks,
Pavan