Re: missing indexes in indexlist with partitioned tables

Alvaro Herrera <alvherre@alvh.no-ip.org>

From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: David Rowley <dgrowleyml@gmail.com>
Cc: Arne Roland <A.Roland@index.de>, Amit Langote <amitlangote09@gmail.com>, pgsql-hackers <pgsql-hackers@postgresql.org>, Zhihong Yu <zyu@yugabyte.com>, Julien Rouhaud <rjuju123@gmail.com>
Date: 2022-09-17T18:37:01Z
Lists: pgsql-hackers
On 2022-Sep-16, David Rowley wrote:

> I kinda disagree with Alvaro's fix in 05fb5d661. I think indexlist is
> the place to store these details.  That commit added the following
> comment:
> 
> /*
> * Ignore partitioned indexes, since they are not usable for
> * queries.
> */
> 
> But neither are hypothetical indexes either, yet they're added to
> RelOptInfo.indexlist.
> 
> I think the patch should be changed so that the existing list is used
> and we find another fix for the problems Alvaro fixed in 05fb5d661.
> Unfortunately, there was no discussion marked on that commit message,
> so it's not quite clear what the problem was. I'm unsure if there was
> anything other than CLUSTER that was broken.

After a bit of trawling through the archives, I found it here:
https://www.postgresql.org/message-id/20180124162006.pmapfiznhgngwtjf%40alvherre.pgsql
I think there was insufficient discussion and you're probably right that
it wasn't the best fix.  I don't object to finding another fix.

-- 
Álvaro Herrera               48°01'N 7°57'E  —  https://www.EnterpriseDB.com/



Commits

  1. Allow left join removals and unique joins on partitioned tables

  2. Add index on pg_publication_rel.prpubid