From: Chao Li <li.evan.chao@gmail.com>
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Subject: Re: SQL:2023 JSON simplified accessor support
Date: Tue, 2 Sep 2025 10:43:58 +0800
In-Reply-To: 
 <CAK98qZ2E-uc10nf4SR9K7Z8VeDPLeTW-+xtdh5Zej54X=mgZcA@mail.gmail.com>
Cc: jian he <jian.universality@gmail.com>,
 Nikita Malakhov <hukutoc@gmail.com>,
 Vik Fearing <vik@postgresfriends.org>,
 Mark Dilger <mark.dilger@enterprisedb.com>,
 Matheus Alcantara <matheusssilv97@gmail.com>,
 Peter Eisentraut <peter@eisentraut.org>,
 Andrew Dunstan <andrew@dunslane.net>,
 Nikita Glukhov <glukhov.n.a@gmail.com>,
 PostgreSQL Hackers <pgsql-hackers@postgresql.org>,
 "David E. Wheeler" <david@justatheory.com>
To: Alexandra Wang <alexandra.wang.oss@gmail.com>
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Hi Alex,

Thank you so much for such a detailed explanation.

> On Aug 30, 2025, at 08:53, Alexandra Wang =
<alexandra.wang.oss@gmail.com> wrote:
>=20
>=20
>=20
> I hope this long explanation helps!
>=20
> [1] =
https://www.postgresql.org/docs/current/functions-json.html#SQLJSON-QUERY-=
FUNCTIONS
>=20
>=20


I used to only use the =E2=80=9C->=E2=80=9D and =E2=80=9C->>=E2=80=9D =
accessors for jsonb statements. After some research, I think my =
misunderstanding was about the slice operator [x:y]. I thought it could =
return a new array, however it actually returns a sequence.

I revisited the patch diffs again, and got a few other comments. Let me =
raise them in a separate email.

Regards,
--
Chao Li (Evan)
HighGo Software Co., Ltd.
https://www.highgo.com/


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<html><head><meta http-equiv=3D"content-type" content=3D"text/html; =
charset=3Dutf-8"></head><body style=3D"overflow-wrap: break-word; =
-webkit-nbsp-mode: space; line-break: after-white-space;">Hi =
Alex,<div><br></div><div>Thank you so much for such a detailed =
explanation.<br id=3D"lineBreakAtBeginningOfMessage"><div><br><blockquote =
type=3D"cite"><div>On Aug 30, 2025, at 08:53, Alexandra Wang =
&lt;alexandra.wang.oss@gmail.com&gt; wrote:</div><br =
class=3D"Apple-interchange-newline"><div><div =
dir=3D"ltr"><div><br></div><div class=3D"gmail_quote =
gmail_quote_container"><div><br></div><div>I hope this long explanation =
helps!<br></div><div><br></div><div>[1]&nbsp;<a =
href=3D"https://www.postgresql.org/docs/current/functions-json.html#SQLJSO=
N-QUERY-FUNCTIONS">https://www.postgresql.org/docs/current/functions-json.=
html#SQLJSON-QUERY-FUNCTIONS</a></div><div><br></div><div><br></div></div>=
</div>
</div></blockquote></div><div><br></div><div>I used to only use the =
=E2=80=9C-&gt;=E2=80=9D and =E2=80=9C-&gt;&gt;=E2=80=9D accessors for =
jsonb statements. After some research, I think my misunderstanding was =
about the slice operator [x:y]. I thought it could return a new array, =
however it actually returns a sequence.</div><div><br></div><div>I =
revisited the patch diffs again, and got a few other comments. Let me =
raise them in a separate email.</div><div><br></div>Regards,<br><div>
<div dir=3D"auto" style=3D"caret-color: rgb(0, 0, 0); color: rgb(0, 0, =
0); letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none; overflow-wrap: =
break-word; -webkit-nbsp-mode: space; line-break: =
after-white-space;"><div>--</div><div>Chao Li (Evan)<br>HighGo Software =
Co., Ltd.<br>https://www.highgo.com/</div><div><br></div></div><br =
class=3D"Apple-interchange-newline"><br =
class=3D"Apple-interchange-newline">

</div>
<br></div></body></html>=

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