Re: function calls optimization

From: Andres Freund <andres(at)anarazel(dot)de>
To: Andrzej Barszcz <abusinf(at)gmail(dot)com>,Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: pgsql-hackers(at)lists(dot)postgresql(dot)org
Subject: Re: function calls optimization
Date: 2019-10-31 15:52:53
Message-ID: ACC66C12-F3AE-4B90-A2CC-4E2332C663E8@anarazel.de
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

Hi,

On October 31, 2019 8:51:11 AM PDT, Andrzej Barszcz <abusinf(at)gmail(dot)com> wrote:
>x <> 0 is evaluated first, 1/x only when x <> 0, not ?
>
>czw., 31 paź 2019 o 16:45 Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> napisał(a):
>
>> Andres Freund <andres(at)anarazel(dot)de> writes:
>> > Potentially related note: for nodes like seqscan, combining the
>qual and
>> projection processing into one expression seems to be a noticable win
>(at
>> least when taking care do emit two different sets of deform
>expression
>> steps).
>>
>> There's just one problem: that violates SQL semantics, and not in
>> a small way.
>>
>> select 1/x from tab where x <> 0

On postgres lists the policy is to reply below the quoted bit, and to trim the quote appropriately.

Andres
--
Sent from my Android device with K-9 Mail. Please excuse my brevity.

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Jim Finnerty 2019-10-31 15:56:22 Re: function calls optimization
Previous Message Igor Calabria 2019-10-31 15:51:17 Adding percentile metrics to pg_stat_statements module