From: Chengpeng Yan <chengpeng_yan@outlook.com>
To: David Rowley <dgrowleyml@gmail.com>
CC: PostgreSQL-development <pgsql-hackers@postgresql.org>, cca5507
	<cca5507@qq.com>, Tom Lane <tgl@sss.pgh.pa.us>
Subject: Re: [PATCH] Fix hashed ScalarArrayOp semantics for NULL LHS with
 non-strict comparators
Thread-Topic: [PATCH] Fix hashed ScalarArrayOp semantics for NULL LHS with
 non-strict comparators
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 AQHczaEqi+5p9wMBTka3ciLQwzUU6rXmX14AgAD10wCAACpDAIAERiEAgABTKACAABE3gIAAA/AA
Date: Thu, 23 Apr 2026 05:47:01 +0000
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> On Apr 23, 2026, at 13:32, David Rowley <dgrowleyml@gmail.com> wrote:
>=20
> I thought of it, but didn't do it as it meant having to keep a bit
> more state to track if we've filled the cache yet, plus the extra
> costs incurred to check if we've done it yet that would have to be
> paid for every NULL lookup. We currently have to check if the hash
> table has been set up already, so I felt more comfortable installing
> the new code in with that.


That makes sense to me. I agree that tying it to the existing hash-table
setup is the simpler place to do it, and avoids adding extra state plus
another check on each NULL lookup.

So I am fine with keeping it as-is.
--
Best regards,
Chengpeng Yan