Re: Optimization for updating foreign tables in Postgres FDW

On 16-04-2015 PM 07:50, Etsuro Fujita wrote:
>> The EXPLAIN output has also been improved as discussed in [1].
> 
> I noticed that the EXPLAIN for a pushed-down update (delete) on inheritance
> childs doubly displays "Foreign Update" ("Foreign Delete"), one for
> ForeignScan and the other for ModifyTable.  Here is an example:
> 
> postgres=# explain verbose update parent set c1 = c1;
>                                   QUERY PLAN
> ------------------------------------------------------------------------------
>  Update on public.parent  (cost=0.00..364.54 rows=4819 width=10)
>    Update on public.parent
>    Foreign Update on public.ft1
>    Foreign Update on public.ft2
>    ->  Seq Scan on public.parent  (cost=0.00..0.00 rows=1 width=10)
>          Output: parent.c1, parent.ctid
>    ->  Foreign Update on public.ft1  (cost=100.00..182.27 rows=2409 width=10)
>          Remote SQL: UPDATE public.t1 SET c1 = c1
>    ->  Foreign Update on public.ft2  (cost=100.00..182.27 rows=2409 width=10)
>          Remote SQL: UPDATE public.t2 SET c1 = c1
> (10 rows)
> 
> Should we do something?  Suggestions are welcome.
> 

From what I see in Tom's commit message[0] for FTI patch, this shouldn't be,
right?

To be specific, there should be "Foreign Scan" there as per the commit. Am I
missing something?

Thanks,
Amit

[1]
http://git.postgresql.org/gitweb/?p=postgresql.git;a=commitdiff;h=cb1ca4d800621dcae67ca6c799006de99fa4f0a5