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From: Tom Lane <tgl@sss.pgh.pa.us>
To: "David G. Johnston" <david.g.johnston@gmail.com>
cc: Bruce Momjian <bruce@momjian.us>, Pavlo Golub <pavlo.golub@gmail.com>,
        Laurenz Albe <laurenz.albe@cybertec.at>,
        pgsql-docs@lists.postgresql.org
Subject: Re: COPY manual is ambiguous about column list
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Comments: In-reply-to "David G. Johnston" <david.g.johnston@gmail.com>
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"David G. Johnston" <david.g.johnston@gmail.com> writes:
> Seems better to simply talk about each form independently:

> If a list of columns is specified, <command>COPY TO</command> will only
> copy the data in the specified columns to the file.  <command>COPY
> FROM</command> will, by position (i.e., the number of columns listed must
> match the number of columns in the file), match each file column to the
> named column in the table.  Any additional columns present in the table
> will receive their default value.

+1 for separating it like that, but your middle sentence reads awkwardly
to me.  How about something like

  <command>COPY FROM</command> will match each listed column in the table
  to a file column by position (so the number of columns listed must match
  the number of columns in the file).

			regards, tom lane