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From: Richard Guo <guofenglinux@gmail.com>
Date: Tue, 21 Apr 2026 09:57:34 +0900
Message-ID: <CAMbWs49tDE_niKLr4mzsa2BkX7fkWrorBzWheKTBziZ7z9-AuQ@mail.gmail.com>
Subject: Re: BUG #19418: SQL/JSON JSON_VALUE() does not conform to ISO/IEC
 9075-2:2023(E) 6.34 <JSON value constructor>
To: Amit Langote <amitlangote09@gmail.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Vik Fearing <vik@postgresfriends.org>, lukas.eder@gmail.com, 
	pgsql-bugs@lists.postgresql.org, =?UTF-8?Q?=C3=81lvaro_Herrera?= <alvherre@kurilemu.de>
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On Mon, Apr 20, 2026 at 6:05=E2=80=AFPM Amit Langote <amitlangote09@gmail.c=
om> wrote:
> Agreed that v4 is the better direction.

Thanks for review!

> The comment on orig_query could say "not walked" a bit more helpfully, e.=
g.
>
> Node       *orig_query;     /* for deparse only; not walked (func is) */

Sounds good.

> I also noticed that the comment for 'func' is incomplete as it is and
> this change warrants an update. Maybe a bit long, but how about:
>
>     Expr       *func;           /* expression producing the result:
>                                  * Aggref/WindowFunc for *AGG,
>                                  * CoalesceExpr for ARRAY_QUERY,
>                                  * json[b]_xxx() call for remaining types=
 */

It seems that func is NULL for "remaining types".  How about we go
with:

  Expr       *func;           /* executable expression:
                               * Aggref/WindowFunc for *AGG,
                               * CoalesceExpr for ARRAY_QUERY,
                               * NULL for other types (executor calls
                               * underlying json[b]_xxx() functions) */

(maybe we should place the multi-line comment above the field.)

- Richard