Re: add_partial_path() may remove dominated path but still in use

Robert Haas <robertmhaas@gmail.com>

From: Robert Haas <robertmhaas@gmail.com>
To: Kohei KaiGai <kaigai@heterodb.com>
Cc: Kyotaro HORIGUCHI <horiguchi.kyotaro@lab.ntt.co.jp>, Tom Lane <tgl@sss.pgh.pa.us>, Pg Hackers <pgsql-hackers@postgresql.org>
Date: 2019-01-10T20:52:02Z
Lists: pgsql-hackers
On Wed, Jan 9, 2019 at 12:44 AM Kohei KaiGai <kaigai@heterodb.com> wrote:
> So, is it sufficient if set_rel_pathlist_hook is just relocated in
> front of the generate_gather_paths?
> If we have no use case for the second hook, here is little necessity
> to have the post_rel_pathlist_hook() here.
> (At least, PG-Strom will use the first hook only.)

+1.  That seems like the best way to be consistent with the principle
that we need to have all the partial paths before generating any
Gather paths.

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


Commits

  1. Call set_rel_pathlist_hook before generate_gather_paths, not after.