Обсуждение: Odd oid-system-column handling in postgres_fdw

Hi,

PG9.5 allows us to add an oid system column to foreign tables, using
ALTER FOREIGN TABLE SET WITH OIDS, but currently, that column reads as
zeroes in postgres_fdw.  That seems to me like a bug.  So, I'd like to
propose to fix that, by retrieving that column from the remote server
when requested.  I'm attaching a proposed patch for that.

Best regards,
Etsuro Fujita

On 2016/03/16 16:25, Etsuro Fujita wrote:
> PG9.5 allows us to add an oid system column to foreign tables, using
> ALTER FOREIGN TABLE SET WITH OIDS, but currently, that column reads as
> zeroes in postgres_fdw.  That seems to me like a bug.  So, I'd like to
> propose to fix that, by retrieving that column from the remote server
> when requested.  I'm attaching a proposed patch for that.

I rebased the patch against HEAD.  Updated patch attached.  I don't
think this is a 9.6 issue, but I think this is somewhat related to the
9.6 issue [1] that postgres_fdw join pushdown incorrectly retrieves
system columns other than ctid and oid from the remote server, so ISTM
that it's better to address this in conjunction with [1].

Best regards,
Etsuro Fujita

[1] http://www.postgresql.org/message-id/57035DFC.3050802@lab.ntt.co.jp

On 2016/04/05 17:15, Etsuro Fujita wrote:
> On 2016/03/16 16:25, Etsuro Fujita wrote:
>> PG9.5 allows us to add an oid system column to foreign tables, using
>> ALTER FOREIGN TABLE SET WITH OIDS, but currently, that column reads as
>> zeroes in postgres_fdw.  That seems to me like a bug.  So, I'd like to
>> propose to fix that, by retrieving that column from the remote server
>> when requested.  I'm attaching a proposed patch for that.

> I rebased the patch against HEAD.  Updated patch attached.

I'll add this to the next CF.

Best regards,
Etsuro Fujita

On Wed, May 11, 2016 at 3:44 AM, Etsuro Fujita
<fujita.etsuro@lab.ntt.co.jp> wrote:
> I'll add this to the next CF.

Makes sense.  I think this is basically a new feature, so let's treat
it that way.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company

On 04/05/2016 11:15 AM, Etsuro Fujita wrote:
> On 2016/03/16 16:25, Etsuro Fujita wrote:
>> PG9.5 allows us to add an oid system column to foreign tables, using
>> ALTER FOREIGN TABLE SET WITH OIDS, but currently, that column reads as
>> zeroes in postgres_fdw.  That seems to me like a bug.  So, I'd like to
>> propose to fix that, by retrieving that column from the remote server
>> when requested.  I'm attaching a proposed patch for that.
>
> I rebased the patch against HEAD.  Updated patch attached.

Committed, thanks!

- Heikki

On 2016/08/26 22:35, Heikki Linnakangas wrote:
> On 04/05/2016 11:15 AM, Etsuro Fujita wrote:
>> On 2016/03/16 16:25, Etsuro Fujita wrote:
>>> PG9.5 allows us to add an oid system column to foreign tables, using
>>> ALTER FOREIGN TABLE SET WITH OIDS, but currently, that column reads as
>>> zeroes in postgres_fdw.  That seems to me like a bug.  So, I'd like to
>>> propose to fix that, by retrieving that column from the remote server
>>> when requested.  I'm attaching a proposed patch for that.

>> I rebased the patch against HEAD.  Updated patch attached.

> Committed, thanks!

Thank you for taking the time to commit this patch!

Best regards,
Etsuro Fujita