Horton

Re: SQL:2023 JSON simplified accessor support

Chao Li <li.evan.chao@gmail.com>

View thread
From: Chao Li <li.evan.chao@gmail.com>
To: Alexandra Wang <alexandra.wang.oss@gmail.com>
Cc: PostgreSQL Hackers <pgsql-hackers@postgresql.org>, Nikita Glukhov <glukhov.n.a@gmail.com>, 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>, "David E. Wheeler" <david@justatheory.com>
Date: 2025-09-24T06:37:43Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Add test coverage for indirection transformation

  2. Fix typo in comment

  3. Implementation of subscripting for jsonb


> On Sep 24, 2025, at 09:05, Alexandra Wang <alexandra.wang.oss@gmail.com> wrote:
> 
> This is the expected behavior for array subscripting, and my patch
> doesn't change that. I don't think this is a problem. With or without
> my patch, you can avoid the ERROR by adding parentheses:
> 
> test=# select ((p).meta[1])['a'] from people; meta ------ 30 (1 row)
> 

Okay, make sense.


>> 2 - 0002
>> ```
>> +		/* Collect leading A_Indices subscripts */
>> +		foreach(lc, indirection)
>> +		{
>> +			Node	   *n = lfirst(lc);
>> +
>> +			if (IsA(n, A_Indices))
>> +			{
>> +				A_Indices  *ai = (A_Indices *) n;
>> +
>> +				subscriptlist = lappend(subscriptlist, n);
>> +				if (ai->is_slice)
>> +					isSlice = true;
>> +			}
>> +			else
>> +				break;
>> ```
>> 
>> We can break after “isSlice=true”.
> 
> Why? We still want to get the whole prefix list of A_Indices. 

Ah, I just realized the main goal of the foreach loop is to build a new “subscrptlist”. In that case, it should not break.

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