Re: Optimization for updating foreign tables in Postgres FDW

On Thu, Mar 24, 2016 at 1:02 PM, Etsuro Fujita
<fujita(dot)etsuro(at)lab(dot)ntt(dot)co(dot)jp> wrote:
> On 2016/03/24 11:14, Michael Paquier wrote:
>>
>> On Wed, Mar 23, 2016 at 10:05 PM, Thom Brown <thom(at)linux(dot)com> wrote:
>>>
>>> I've noticed that you now can't cancel a query if there's DML pushdown
>>> to a foreign server. This previously worked while it was sending
>>> individual statements as it interrupted and rolled it back.
>>>
>>> Here's what the local server sees when trying to cancel:
>>>
>>> # DELETE FROM remote.contacts;
>>> ^CCancel request sent
>>> DELETE 5000000
>>>
>>> This should probably be fixed.
>
>
>> Looking at what has been committed, execute_dml_stmt is using
>> PQexecParams, so we'd want to use an asynchronous call and loop on
>> PQgetResult with CHECK_FOR_INTERRUPTS() in it.
>
>
> Will fix.
>
> Thanks for the report, Thom! Thanks for the advice, Michael!

I am adding that to the list of open items of 9.6 to not forget about it.
--
Michael