Message-ID: <7a60faf6-e7f1-419d-aee6-10a78ea2fe81@joeconway.com>
Date: Tue, 5 Dec 2023 16:46:50 -0500
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Subject: Re: Emitting JSON to file using COPY TO
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To: Andrew Dunstan <andrew@dunslane.net>, Davin Shearer <davin@apache.org>,
 PostgreSQL-development <pgsql-hackers@postgresql.org>
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From: Joe Conway <mail@joeconway.com>
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Precedence: bulk

On 12/5/23 16:20, Andrew Dunstan wrote:
> On 2023-12-05 Tu 16:09, Joe Conway wrote:
>> On 12/5/23 16:02, Joe Conway wrote:
>>> On 12/5/23 15:55, Andrew Dunstan wrote:
>>>> and in any other case (e.g. LINES) I can't see why you
>>>> would have them.
>>
>> Oh I didn't address this -- I saw examples in the interwebs of MSSQL 
>> server I think [1] which had the non-array with commas import and 
>> export style. It was not that tough to support and the code as written 
>> already does it, so why not?
> 
> That seems quite absurd, TBH. I know we've catered for some absurdity in
> the CSV code (much of it down to me), so maybe we need to be liberal in
> what we accept here too. IMNSHO, we should produce either a single JSON
> document (the ARRAY case) or a series of JSON documents, one per row
> (the LINES case).


So your preference would be to not allow the non-array-with-commas case 
but if/when we implement COPY FROM we would accept that format? As in 
Postel'a law ("be conservative in what you do, be liberal in what you 
accept from others")?

-- 
Joe Conway
PostgreSQL Contributors Team
RDS Open Source Databases
Amazon Web Services: https://aws.amazon.com