Re: Garbled comment in postgresGetForeignJoinPaths

From: Robert Haas <robertmhaas(at)gmail(dot)com>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: "pgsql-hackers(at)postgresql(dot)org" <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: Garbled comment in postgresGetForeignJoinPaths
Date: 2017-08-16 17:20:36
Message-ID: CA+TgmoY377WU7N-Z6D5iCRWVJWY9G+RzaomD+eOX28dOLEnyeQ@mail.gmail.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

On Wed, Aug 16, 2017 at 12:31 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> postgres_fdw.c around line 4500:
>
> /*
> * If there is a possibility that EvalPlanQual will be executed, we need
> * to be able to reconstruct the row using scans of the base relations.
> * GetExistingLocalJoinPath will find a suitable path for this purpose in
> * the path list of the joinrel, if one exists. We must be careful to
> * call it before adding any ForeignPath, since the ForeignPath might
> * dominate the only suitable local path available. We also do it before
> --> * reconstruct the row for EvalPlanQual(). Find an alternative local path
> * calling foreign_join_ok(), since that function updates fpinfo and marks
> * it as pushable if the join is found to be pushable.
> */
>
> Should the marked line simply be deleted? If not, what correction is
> appropriate?

Hmm, wow. My first thought was that it should just say
"reconstructing" rather than "reconstruct", but on further reading I
think you might have the right idea.

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

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Robert Haas 2017-08-16 17:24:36 Re: Atomics for heap_parallelscan_nextpage()
Previous Message Heikki Linnakangas 2017-08-16 17:19:29 Re: Atomics for heap_parallelscan_nextpage()