Re: Emitting JSON to file using COPY TO

On 12/7/23 09:11, David G. Johnston wrote:
> Those are all the same breakage though - if truly interpreted as data
> rows the protocol is basically written such that the array format is not
> supportable and only the lines format can be used.  Hence my “format 0
> doesn’t work” comment for array output and we should explicitly add
> format 2 where we explicitly decouple lines of output from rows of
> data.  That said, it would seem in practice format 0 already decouples
> them and so the current choice of the brackets on their own lines is
> acceptable.
>
> I’d prefer to keep them on their own line.

WFM ¯\_(ツ)_/¯

I am merely responding with options to the many people opining on the
thread.

> I also don’t know why you introduced another level of object nesting
> here.  That seems quite undesirable.

I didn't add anything. It is an artifact of the particular query I wrote
in the copy to statement (I did "select ss from ss" instead of "select *
from ss"), mea culpa.

This is what the latest patch, as written today, outputs:
8<----------------------
copy
(select 1, g.i from generate_series(1, 3) g(i))
to stdout (format json, force_array);
[
{"?column?":1,"i":1}
,{"?column?":1,"i":2}
,{"?column?":1,"i":3}
]
8<----------------------

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