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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Joe Conway <mail@joeconway.com>
cc: Andrew Dunstan <andrew@dunslane.net>, Davin Shearer <davin@apache.org>,
        PostgreSQL-development <pgsql-hackers@postgresql.org>
Subject: Re: Emitting JSON to file using COPY TO
In-reply-to: <bbf922c5-f571-483e-a2c6-2730b02183fe@joeconway.com>
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Comments: In-reply-to Joe Conway <mail@joeconway.com>
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Precedence: bulk

Joe Conway <mail@joeconway.com> writes:
> I believe this is ready to commit unless there are further comments or 
> objections.

I thought we were still mostly at proof-of-concept stage?

In particular, has anyone done any performance testing?
I'm concerned about that because composite_to_json() has
zero capability to cache any metadata across calls, meaning
there is going to be a large amount of duplicated work
per row.

			regards, tom lane