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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Bruce Momjian <bruce@momjian.us>
cc: "David G. Johnston" <david.g.johnston@gmail.com>,
        Pavlo Golub <pavlo.golub@gmail.com>,
        Laurenz Albe <laurenz.albe@cybertec.at>,
        "pgsql-docs@lists.postgresql.org" <pgsql-docs@lists.postgresql.org>
Subject: Re: COPY manual is ambiguous about column list
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Comments: In-reply-to Bruce Momjian <bruce@momjian.us>
	message dated "Fri, 20 Dec 2019 08:45:41 -0500"
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Bruce Momjian <bruce@momjian.us> writes:
> OK, how is this?

I do not like the phrasing of

    If a column list is
    specified in <command>COPY FROM</command>, the number and position of
    the columns must match those fields in the file.

I'm not quite sure why, but that reads to me as implying that the COPY
will identify columns of the file by name and match them up.  Or at
least it could be read that way by somebody who was predisposed to
believe it.  I'd go with something more like

    If a column list is
    specified in <command>COPY FROM</command>, only the listed columns
    are read from the file (whose fields must match the column list).

			regards, tom lane