From: Tom Lane <tgl@sss.pgh.pa.us>
To: Alexander Korotkov <a.korotkov@postgrespro.ru>
Cc: Nikita Glukhov <n.gluhov@postgrespro.ru>
Cc: Fabien COELHO <coelho@cri.ensmp.fr>
Cc: PostgreSQL Hackers <pgsql-hackers@postgresql.org>
Subject: Re: Add missing operator <->(box, point)
Date: Tue, 02 Jul 2019 15:13:30 -0400
Message-ID: <4682.1562094810@sss.pgh.pa.us> (raw)
In-Reply-To: <CAPpHfdtq4+AhjBhjEMkeLqi46pz-dEUs3=SQG-_nSPsw+hHAyA@mail.gmail.com>
References: <f71ba19d-d989-63b6-f04a-abf02ad9345d@postgrespro.ru>
<alpine.DEB.2.21.1904201526100.29102@lancre>
<6935.1562040096@sss.pgh.pa.us>
<2fe442bd-4e0c-56ba-eb62-f1b51f6b17f3@postgrespro.ru>
<CAPpHfdtq4+AhjBhjEMkeLqi46pz-dEUs3=SQG-_nSPsw+hHAyA@mail.gmail.com>
Alexander Korotkov <a.korotkov@postgrespro.ru> writes:
> On Tue, Jul 2, 2019 at 9:19 PM Nikita Glukhov <n.gluhov@postgrespro.ru> wrote:
>> We could use commuted "const <-> var" operators for kNN searches, but the
>> current implementation requires the existence of "var <-> const" operators, and
>> order-by-op clauses are rebuilt using them (see match_clause_to_ordering_op()
>> at /src/backend/optimizer/path/indxpath.c).
> But probably it's still worth to just add commutator for every <->
> operator and close this question.
Yeah, I was just thinking that it was weird not to have the commutator
operators, independently of indexing considerations. Seems like a
usability thing.
regards, tom lane
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To: pgsql-hackers@postgresql.org
Cc: tgl@sss.pgh.pa.us, a.korotkov@postgrespro.ru, n.gluhov@postgrespro.ru, coelho@cri.ensmp.fr
Subject: Re: Add missing operator <->(box, point)
In-Reply-To: <4682.1562094810@sss.pgh.pa.us>
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