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From: Davin Shearer <davin@apache.org>
Date: Tue, 5 Dec 2023 18:45:24 -0500
Message-ID: <CALvfUkCNS80P2EH8rOJ3uoTZDJX3MEhk8aOD2iVJqLvveG8zNw@mail.gmail.com>
Subject: Re: Emitting JSON to file using COPY TO
To: Joe Conway <mail@joeconway.com>
Cc: Andrew Dunstan <andrew@dunslane.net>, 
	PostgreSQL-development <pgsql-hackers@postgresql.org>
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> Am I understanding something incorrectly?

No, you've got it.  You already covered the concerns there.

> 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).

For what it's worth, I agree with Andrew on this.  I also agree with COPY
FROM allowing for potentially bogus commas at the end of non-arrays for
interop with other products, but to not do that in COPY TO (unless there is
some real compelling case to do so).  Emitting bogus JSON (non-array with
commas) feels wrong and would be nice to not perpetuate that, if possible.

Thanks again for doing this.  If I can be of any help, let me know.
If\When this makes it into the production product, I'll be using this
feature for sure.

-Davin

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<div dir=3D"ltr"><div dir=3D"ltr"><span style=3D"color:rgb(80,0,80)">&gt;=
=C2=A0</span>Am I understanding something incorrectly?</div><div dir=3D"ltr=
"><br></div><div>No, you&#39;ve got it.=C2=A0 You already covered the conce=
rns there.</div><div dir=3D"ltr"><br></div><div dir=3D"ltr"><span style=3D"=
color:rgb(80,0,80)">&gt; That seems quite absurd, TBH. I know we&#39;ve cat=
ered for some absurdity in</span><br style=3D"color:rgb(80,0,80)"><span sty=
le=3D"color:rgb(80,0,80)">&gt; the CSV code (much of it down to me), so may=
be we need to be liberal in</span><br style=3D"color:rgb(80,0,80)"><span st=
yle=3D"color:rgb(80,0,80)">&gt; what we accept here too. IMNSHO, we should =
produce either a single JSON</span><br style=3D"color:rgb(80,0,80)"><span s=
tyle=3D"color:rgb(80,0,80)">&gt; document (the ARRAY case) or a series of J=
SON documents, one per row</span><br style=3D"color:rgb(80,0,80)"><span sty=
le=3D"color:rgb(80,0,80)">&gt; (the LINES case).</span></div><div dir=3D"lt=
r"><span style=3D"color:rgb(80,0,80)"><br></span></div><div>For what it&#39=
;s worth, I agree with Andrew on this.=C2=A0 I also agree with COPY FROM al=
lowing for potentially bogus commas at the end of non-arrays for interop wi=
th other products, but to not do that in COPY TO (unless there is some real=
 compelling case to do so).=C2=A0 Emitting bogus JSON (non-array with comma=
s) feels wrong and would be nice to=C2=A0not perpetuate that, if possible.<=
/div><div><br></div><div>Thanks again for doing this.=C2=A0 If I can be of =
any help, let me know.=C2=A0 If\When this makes it into the production prod=
uct, I&#39;ll be using this feature for sure.</div><div><br></div><div>-Dav=
in</div><div><br></div><div><br></div></div>

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