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From: David Rowley <dgrowleyml@gmail.com>
Date: Mon, 20 Feb 2023 22:51:40 +1300
Message-ID: <CAApHDvoVn51T=y8Ty02SnC9m-rh_yuKUaZQknBugCsGqK9FdoA@mail.gmail.com>
Subject: Re: Introduce list_reverse() to make lcons() usage less inefficient
To: Andres Freund <andres@anarazel.de>
Cc: PostgreSQL Developers <pgsql-hackers@lists.postgresql.org>
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On Fri, 17 Feb 2023 at 16:35, David Rowley <dgrowleyml@gmail.com> wrote:
>
> On Fri, 17 Feb 2023 at 13:23, Andres Freund <andres@anarazel.de> wrote:
> > But wouldn't an even cheaper way here be to iterate over the children in
> > reverse order when match_partition_order_desc? We can do that efficiently
> > now. Looks like we don't have a readymade helper for it, but it'd be easy
> > enough to add or open code.
>
> That seems fair.  I think open coding is a better option.  I had a go
> at foreach_reverse recently and decided to keep clear of it due to
> behavioural differences with foreach_delete_current().

I've pushed a patch for this now. Thank you for the idea.

David