Re: Problem while updating a foreign table pointing to a partitioned table on foreign server

On Tue, Jun 26, 2018 at 9:59 AM, Kyotaro HORIGUCHI
<horiguchi(dot)kyotaro(at)lab(dot)ntt(dot)co(dot)jp> wrote:
>
>> But good thing is because of join and aggregate
>> push-down we already have ability to push arbitrary kinds of nodes
>> down to the foreign server through the targetlist. We should be able
>> to leverage that capability. It looks like a lot of change, which
>> again doesn't seem to be back-portable.
>
> After some struggles as you know, I agree to the opinion. As my
> first impression, giving (physical) base relations (*1) an
> ability to have junk attribute is rather straightforward.

By giving base relations an ability to have junk attribute you mean to
add junk attribute in the targetlist of DML, something like
postgresAddForeignUpdateTargets(). You seem to be fine with the new
node approach described above. Just confirm.

>
> Well, is our conclusion here like this?
>
> - For existing versions, check the errorneous situation and ERROR out.
> (documentaion will be needed.)
>
> - For 12, we try the above thing.

I think we have to see how invasive the fix is, and whether it's
back-portable. If it's back-portable, we back-port it and the problem
is fixed in previous versions as well. If not, we fix previous
versions to ERROR out instead of corrupting the database.

--
Best Wishes,
Ashutosh Bapat
EnterpriseDB Corporation
The Postgres Database Company