Re: constraint exclusion and nulls in IN (..) clause

Robert Haas <robertmhaas@gmail.com>

From: Robert Haas <robertmhaas@gmail.com>
To: Ashutosh Bapat <ashutosh.bapat@enterprisedb.com>
Cc: Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>, Pg Hackers <pgsql-hackers@postgresql.org>
Date: 2018-02-06T21:10:03Z
Lists: pgsql-hackers
On Sun, Feb 4, 2018 at 11:20 PM, Ashutosh Bapat
<ashutosh.bapat@enterprisedb.com> wrote:
> On Thu, Feb 1, 2018 at 2:23 PM, Amit Langote
> <Langote_Amit_f8@lab.ntt.co.jp> wrote:
>> Yeah, the patch in its current form is wrong, because it will give wrong
>> answers if the operator being used in a SAOP is non-strict.  I modified
>> the patch to consider operator strictness before doing anything with nulls.
>
> That's fine, but I am not sure whether this fits constraint
> exclusion's charter. Please add this patch to the next commitfest so
> that we can have a better opinion.

It seems like a perfectly reasonable extension of the existing
functionality to me.  (I have, at present, no opinion on the patch
itself.)

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company


Commits

  1. Improve predtest.c's handling of cases with NULL-constant inputs.