From: Tom Lane <tgl@sss.pgh.pa.us>
To: Richard Guo <guofenglinux@gmail.com>
cc: Tender Wang <tndrwang@gmail.com>, runyuan@berkeley.edu,
        pgsql-bugs@lists.postgresql.org
Subject: Re: BUG #19046: Incorrect result when using json_array() with column
 reference in subquery combined with RIGHT JOIN
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Comments: In-reply-to Richard Guo <guofenglinux@gmail.com>
	message dated "Thu, 11 Sep 2025 12:10:15 +0900"
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Date: Wed, 10 Sep 2025 23:16:33 -0400
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Richard Guo <guofenglinux@gmail.com> writes:
> I tested JsonExpr, which is the representation of json_value,
> json_query and json_exists.  It seems that they could not produce
> non-NULL output with a NULL input.  So we are good on that front.

Seems like we ought to actually look at the relevant code, not
try to test our way to an understanding of it.

			regards, tom lane