Re: Join push-down support for foreign tables

> On 2015/03/03 21:34, Shigeru Hanada wrote:
> > I rebased "join push-down" patch onto Kaigai-san's Custom/Foreign Join
> > v6 patch.
>
> Thanks for the work, Hanada-san and KaiGai-san!
>
> Maybe I'm missing something, but did we agree to take this approach, ie,
> "join push-down" on top of custom join? There is a comment ahout that
> [1]. I just thought it'd be better to achieve a consensus before
> implementing the feature further.
>
It is not correct. The join push-down feature is not implemented
on top of the custom-join feature, however, both of them are 99%
similar on both of the concept and implementation.
So, we're working to enhance foreign/custom-join interface together,
according to Robert's suggestion [3], using postgres_fdw extension
as a minimum worthwhile example for both of foreign/custom-scan.

[3] http://bit.ly/1w1PoDU

> > but still the patch
> > has an issue about joins underlying UPDATE or DELETE. Now I'm working
> > on fixing this issue.
>
> Is that something like "UPDATE foo ... FROM bar ..." where both foo and
> bar are remote? If so, I think it'd be better to push such an update
> down to the remote, as discussed in [2], and I'd like to work on that
> together!
>
Hanada-san, could you give us test query to reproduce the problem
above? I and Fujita-san can help to investigate the problem from
different standpoints for each.

> Sorry for having been late for the party.
>
We are still in the party.

Thanks,
--
NEC OSS Promotion Center / PG-Strom Project
KaiGai Kohei <kaigai(at)ak(dot)jp(dot)nec(dot)com>