Horton

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

Emre Hasegeli <emre@hasegeli.com>

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From: Emre Hasegeli <emre@hasegeli.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>, Ashutosh Bapat <ashutosh.bapat@enterprisedb.com>, Pg Hackers <pgsql-hackers@postgresql.org>
Date: 2018-03-21T10:22:03Z
Lists: pgsql-hackers 
> After further thought, it seems like the place to deal with this is
> really operator_predicate_proof(), as in the attached draft patch
> against HEAD.  This passes the smell test for me, in the sense that
> it's an arguably correct and general extension of the proof rules,
> but it could use more testing.

I am not sure if we are covering the case when clause_const and
pred_const are both NULL.  In this case, we should be able to return
true only by checking op_strict(pred_op) or maybe even without
checking that.  Am I mistaken?

Commits

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