Re: function calls optimization

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От Andres Freund
Тема Re: function calls optimization
Дата
Msg-id ACC66C12-F3AE-4B90-A2CC-4E2332C663E8@anarazel.de
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Ответ на Re: function calls optimization  (Andrzej Barszcz <abusinf@gmail.com>)
Ответы Re: function calls optimization  (Andrzej Barszcz <abusinf@gmail.com>)
Список pgsql-hackers
Hi,

On October 31, 2019 8:51:11 AM PDT, Andrzej Barszcz <abusinf@gmail.com> wrote:
>x <> 0 is evaluated first, 1/x only when x <> 0, not ?
>
>czw., 31 paź 2019 o 16:45 Tom Lane <tgl@sss.pgh.pa.us> napisał(a):
>
>> Andres Freund <andres@anarazel.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.



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