Re: Odd system-column handling in postgres_fdw join pushdown patch

From: Etsuro Fujita <fujita(dot)etsuro(at)lab(dot)ntt(dot)co(dot)jp>
To: Ashutosh Bapat <ashutosh(dot)bapat(at)enterprisedb(dot)com>
Cc: Robert Haas <robertmhaas(at)gmail(dot)com>, "pgsql-hackers(at)postgresql(dot)org" <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: Odd system-column handling in postgres_fdw join pushdown patch
Date: 2016-03-29 06:37:06
Views: Raw Message | Whole Thread | Download mbox | Resend email
Lists: pgsql-hackers

On 2016/03/25 17:16, Etsuro Fujita wrote:
> The approach that we discussed would minimize the code for the FDW
> author to write, by providing the support functions you proposed. I'll
> post a patch for that early next week.

I added two helper functions: GetFdwScanTupleExtraData and
FillFdwScanTupleSysAttrs. The FDW author could use the former to get
info about system attributes other than ctids and oids in fdw_scan_tlist
during BeginForeignScan, and the latter to set values for these system
attributes during IterateForeignScan (InvalidTransactionId for
xmins/xmaxs, InvalidCommandId for cmins/cmaxs, and valid values for
tableoids). Attached is a proposed patch for that. I also slightly
simplified the changes to make_tuple_from_result_row and
conversion_error_callback made by the postgres_fdw join pushdown patch.
What do you think about that?

Best regards,
Etsuro Fujita

Attachment Content-Type Size
postgres-fdw-join-pushdown-syscol-handling-v2.patch application/x-download 21.0 KB

In response to


Browse pgsql-hackers by date

  From Date Subject
Next Message Kyotaro HORIGUCHI 2016-03-29 06:43:07 Re: IF (NOT) EXISTS in psql-completion
Previous Message Michael Paquier 2016-03-29 06:21:19 Re: Re: [COMMITTERS] pgsql: Sync tzload() and tzparse() APIs with IANA release tzcode2016c.