Re: proposal: jsonb_populate_array

Vik Fearing <vik@postgresfriends.org>

From: Vik Fearing <vik@postgresfriends.org>
To: Chapman Flack <chap@anastigmatix.net>, Erik Rijkers <er@xs4all.nl>
Cc: Pavel Stehule <pavel.stehule@gmail.com>, Alvaro Herrera <alvherre@alvh.no-ip.org>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2023-08-15T05:44:36Z
Lists: pgsql-hackers
On 8/14/23 15:47, Chapman Flack wrote:
> On 2023-08-14 09:11, Erik Rijkers wrote:
>>   , '$' returning date[]
> 
> I certainly like that syntax better.
> 
> It's not that the "here's a null to tell you the type I want"
> is terribly unclear, but it seems not to be an idiom I have
> seen a lot of in PostgreSQL before now. Are there other places
> it's currently used that I've overlooked?

It has been used since forever in polymorphic aggregate final functions. 
  I don't mind it there, but I do not like it in general user-facing 
functions.

https://www.postgresql.org/docs/current/sql-createaggregate.html
-- 
Vik Fearing