Re: inherit support for foreign tables - Mailing list pgsql-hackers

From David Fetter
Subject Re: inherit support for foreign tables
Date
Msg-id 20141206170216.GA14211@fetter.org
Whole thread Raw
In response to Re: inherit support for foreign tables  (Etsuro Fujita <fujita.etsuro@lab.ntt.co.jp>)
Responses Re: inherit support for foreign tables  (Etsuro Fujita <fujita.etsuro@lab.ntt.co.jp>)
List pgsql-hackers
On Thu, Dec 04, 2014 at 12:35:54PM +0900, Etsuro Fujita wrote:
> (2014/12/03 19:35), Ashutosh Bapat wrote:
> >On Tue, Dec 2, 2014 at 8:29 AM, Etsuro Fujita
> ><fujita.etsuro@lab.ntt.co.jp <mailto:fujita.etsuro@lab.ntt.co.jp>> wrote:
> 
> >This is not exactly extension of non-inheritance case. non-inheritance
> >case doesn't show two remote SQLs under the same plan node. May be you
> >can rename the label Remote SQL as Remote UPDATE/INSERT/DELETE (or
> >something to that effect) for the DML command and the Foreign plan node
> >should be renamed to Foreign access node or something to indicate that
> >it does both the scan as well as DML. I am not keen about the actual
> >terminology, but I think a reader of plan shouldn't get confused.
> >
> >We can leave this for committer's judgement.
> 
> Thanks for the proposal!  I think that would be a good idea.  But I think
> there would be another idea.  An example will be shown below.  We show the
> update commands below the ModifyTable node, not above the corresponding
> ForeignScan nodes, so maybe less confusing.  If there are no objections of
> you and others, I'll update the patch this way.
> 
> postgres=# explain verbose update parent set a = a * 2 where a = 5;
>                                      QUERY PLAN
> -------------------------------------------------------------------------------------
>  Update on public.parent  (cost=0.00..280.77 rows=25 width=10)
>    On public.ft1
>      Remote SQL: UPDATE public.mytable_1 SET a = $2 WHERE ctid = $1      ^^^^^^^^^^
It occurs to me that the command generated by the FDW might well not
be SQL at all, as is the case with file_fdw and anything else that
talks to a NoSQL engine.

Would it be reasonable to call this "Remote command" or something
similarly generic?

Cheers,
David.
-- 
David Fetter <david@fetter.org> http://fetter.org/
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