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Date: Tue, 28 Nov 2023 08:36:32 +0100
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Subject: Re: Emitting JSON to file using COPY TO
To: Dominique Devienne <ddevienne@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>
Cc: "David G. Johnston" <david.g.johnston@gmail.com>,
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This would be a very special case for COPY. It applies only to a single 
column of JSON values. The original problem can be solved with psql 
--tuples-only as David wrote earlier.


$ psql -tc 'select json_agg(row_to_json(t))
              from (select * from public.tbl_json_test) t;'

  [{"id":1,"t_test":"here's a \"string\""}]


Special-casing any encoding/escaping scheme leads to bugs and harder 
parsing.

Just my 2c.

--
Filip Sedlák