Message-ID: <b67f0fc8f3eb3b798b9c7145b20a0033af2da47e.camel@cybertec.at>
Subject: Re: Please implement a catch-all error handler per row, for COPY
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: me nefcanto <sn.1361@gmail.com>, Greg Sabino Mullane <htamfids@gmail.com>
Cc: "David G. Johnston" <david.g.johnston@gmail.com>, Tom Lane
	 <tgl@sss.pgh.pa.us>, pgsql-general@lists.postgresql.org
Date: Mon, 03 Mar 2025 09:55:03 +0100
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On Mon, 2025-03-03 at 07:14 +0330, me nefcanto wrote:
> The point is, that there is already an `on_error ignore` clause there. Th=
is means that
> somewhere there is a try/catch per row. If I'm wrong, please let me know.

The crucial point that Tom referred to is the "per row".  What is a row?

Imagine you have a COPY FROM statement for a table with three columns,
and the data look like this:

1,Smith,John
2,Lewis,Jerry
Lee
3,Prince
4,Albe,Laurenz

We may be able to guess what is meant, but how shall the machine know
where the line boundaries are, which data to ignore and which to process?

Currently, that is no problem, because errors are only identified
after the data have been successfully parsed.

Yours,
Laurenz Albe