From: | Kevin Grittner <kgrittn(at)gmail(dot)com> |
---|---|
To: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
Cc: | Andres Freund <andres(at)anarazel(dot)de>, Robert Haas <robertmhaas(at)gmail(dot)com>, "pgsql-hackers(at)postgresql(dot)org" <pgsql-hackers(at)postgresql(dot)org> |
Subject: | Re: Implement targetlist SRFs using ROWS FROM() (was Changed SRF in targetlist handling) |
Date: | 2016-09-02 14:41:28 |
Message-ID: | CACjxUsNrhn5CMk25qsGnx-G6_AAkddQSa=k3g_DFVhb2D1-aSQ@mail.gmail.com |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-hackers |
On Fri, Sep 2, 2016 at 9:25 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Andres Freund <andres(at)anarazel(dot)de> writes:
>> Oh, and we've previously re-added that based on
>> complaints. C.f. d543170f2fdd6d9845aaf91dc0f6be7a2bf0d9e7 (and others
>> IIRC).
>
> That one wasn't about row order per se, but I agree that people *will*
> bitch if we change the behavior, especially if we don't provide a way
> to fix it.
They might also bitch if you add any overhead to put rows in a
specific order when they subsequently sort the rows into some
different order. You might even destroy an order that would have
allowed a sort step to be skipped, so you would pay twice -- once
to put them into some "implied" order and then to sort them back
into the order they would have had without that extra effort.
> ORDER BY is not a useful suggestion when there is nothing
> you could order by to get the old behavior.
I'm apparently missing something, because I see a column with the
header "generate_series" in the result set.
--
Kevin Grittner
EDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company
From | Date | Subject | |
---|---|---|---|
Next Message | Tom Lane | 2016-09-02 14:51:15 | Re: Implement targetlist SRFs using ROWS FROM() (was Changed SRF in targetlist handling) |
Previous Message | Tom Lane | 2016-09-02 14:34:54 | Re: Implement targetlist SRFs using ROWS FROM() (was Changed SRF in targetlist handling) |