Re: postgres_fdw: Oddity in pushing down inherited UPDATE/DELETE joins to remote servers

(2018/05/14 9:45), Amit Langote wrote:
> On 2018/05/11 21:48, Etsuro Fujita wrote:
>> (2018/05/11 16:19), Amit Langote wrote:
>>> On 2018/05/11 16:12, Amit Langote wrote:
>>>> Just to clarify, does this problem only arise because there is a pushed
>>>> down join involving the child? That is, does the problem only occur as of
>>>> the following commit:
>>>>
>>>> commit 1bc0100d270e5bcc980a0629b8726a32a497e788
>>>> Author: Robert Haas<rhaas(at)postgresql(dot)org>
>>>> Date: Wed Feb 7 15:34:30 2018 -0500
>>>>
>>>> postgres_fdw: Push down UPDATE/DELETE joins to remote servers.
>>>>
>>>> In other words, do we need to back-patch this up to 9.5 which added
>>>> foreign table inheritance?
>>>
>>> Oops, it should have been clear by the subject line that the problem
>>> didn't exist before that commit. Sorry.
>>
>> No. In theory, I think we could consider this as an older bug added in
>> 9.5, because in case of inherited UPDATE/DELETE, the PlannerInfo passed
>> to PlanForeignModify doesn't match the one the FDW saw at Path creation
>> time, as you mentioned in a previous email, while in case of
>> non-inherited UPDATE/DELETE, the PlannerInfo passed to that function
>> matches the one the FDW saw at that time. I think that's my fault :(.
>
> Ah, I see. Thanks for clarifying.
>
>> But considering there seems to be no field reports on that, I don't
>> think we need back-patching up to 9.5.
>
> Yeah, that might be fine, although it perhaps wouldn't hurt to have the
> code match in all branches.

I don't object to back-patching. Should I remove this from the open
items list for PG11?

Best regards,
Etsuro Fujita