public inbox for [email protected]
help / color / mirror / Atom feedFrom: Bruce Momjian <[email protected]>
To: Peter Geoghegan <[email protected]>
Cc: PostgreSQL-development <[email protected]>
Subject: Re: PG 18 release notes draft committed
Date: Thu, 18 Sep 2025 10:20:51 -0400
Message-ID: <[email protected]> (raw)
In-Reply-To: <[email protected]>
References: <[email protected]>
<CAH2-Wz=2CWXgO1+uyR-VfN3ALMtFnfTtXK-VtkoQQ89ogm=4sg@mail.gmail.com>
<[email protected]>
<CAH2-Wzko57+sT=FcxHHo7jnPLhh35up_5aAvogLtj_D9bATsgQ@mail.gmail.com>
<[email protected]>
<CAH2-Wz=5aGnkPsLH9u1kZED=M8TKvxX2b9XmgdOe+ePO0KxwcQ@mail.gmail.com>
<[email protected]>
<CAH2-Wzk1aYZpsXRP1iz7iBweg55dZPicPBUL50SmtzkF-Rm9ig@mail.gmail.com>
<[email protected]>
On Wed, Sep 17, 2025 at 04:45:14PM -0400, Bruce Momjian wrote:
> On Wed, Sep 17, 2025 at 11:46:58AM -0400, Peter Geoghegan wrote:
> > I suggest the following alternative, which has the merit of being a
> > bit less verbose:
> >
> > "Skip scan allows B-Tree index scans to find the most efficient way of
> > navigating through a multicolumn index when one or more of its columns
> > initially lacks a = condition and comes before a column that is
> > directly used by the query. Such an index scan can now be broken down
> > into multiple "index searches" by generating an implementation level =
> > condition on any underspecified columns. This allows the scan to skip
> > over irrelevant sections of the index, though only when the generated
> > = condition is on a column that has relatively few distinct values."
> >
> > Note that "index searches" is a term that now appears in EXPLAIN ANALYZE output.
>
> I went with this text, which is more "aspirational" rather than
> "proscriptive", and the right level of detail:
>
> This allows multi-column btree indexes to be used in more cases
> such as when there are no restrictions on the first or early
> indexed columns (or they are non-equality ones), and there are
> useful restrictions on later indexed columns.
With our GA release dates close, I committed the attached patch.
--
Bruce Momjian <[email protected]> https://momjian.us
EDB https://enterprisedb.com
Do not let urgent matters crowd out time for investment in the future.
Attachments:
[text/x-diff] master.diff (0B, ../[email protected]/2-master.diff)
download
view thread (147+ messages)
reply
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: [email protected]
Cc: [email protected], [email protected], [email protected]
Subject: Re: PG 18 release notes draft committed
In-Reply-To: <[email protected]>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by agora; see mirroring instructions
for how to clone and mirror all data and code used for this inbox