Re: Fwd: Copy out wording - Mailing list pgsql-hackers

Magnus Hagander wrote:
> On Thu, Sep 3, 2009 at 13:31, Andrew Dunstan<andrew@dunslane.net> wrote:
> >
> >
> > Magnus Hagander wrote:
> >>
> >> Oh, hang on, "the NULL string" refers to the copy parameter? Not a
> >> part of the data? I read it as "a string being NULL". Maybe something
> >> like "the value of the NULL string parameter" to be overly clear for
> >> people like me? :-)
> >>
> >
> > We could change:
> >
> > ? A NULL is output as the NULL string and is not quoted, while a data value
> > ? matching the NULL string is quoted.
> >
> >
> > to
> >
> > ? A NULL is output as the NULL parameter and is not quoted, while a non-NULL
> > data value whose text representation
> > ? matches the NULL parameter is quoted.
> >
> >
> > or something similar. Would that be better?
>
> Yes, much better IMO.

I have applied the attached documentation clarification patch, and
backpatched it to 8.4.X.

--
  Bruce Momjian  <bruce@momjian.us>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

  + If your life is a hard drive, Christ can be your backup. +
Index: doc/src/sgml/ref/copy.sgml
===================================================================
RCS file: /cvsroot/pgsql/doc/src/sgml/ref/copy.sgml,v
retrieving revision 1.87
diff -c -c -r1.87 copy.sgml
*** doc/src/sgml/ref/copy.sgml    5 Sep 2009 23:58:01 -0000    1.87
--- doc/src/sgml/ref/copy.sgml    17 Sep 2009 21:06:59 -0000
***************
*** 550,562 ****
     <para>
      The <literal>CSV</> format has no standard way to distinguish a
      <literal>NULL</> value from an empty string.
!     <productname>PostgreSQL</>'s <command>COPY</> handles this by
!     quoting. A <literal>NULL</> is output as the <literal>NULL</>
!     string and is not quoted, while a data value matching the
!     <literal>NULL</> string is quoted. Therefore, using the default
!     settings, a <literal>NULL</> is written as an unquoted empty
!     string, while an empty string is written with double quotes
!     (<literal>""</>). Reading values follows similar rules. You can
      use <literal>FORCE NOT NULL</> to prevent <literal>NULL</> input
      comparisons for specific columns.
     </para>
--- 550,559 ----
     <para>
      The <literal>CSV</> format has no standard way to distinguish a
      <literal>NULL</> value from an empty string.
!     <productname>PostgreSQL</>'s <command>COPY</> handles this using
!     quoting. A <literal>NULL</> is output as an empty string without
!     quotes, while an empty string data value is double-quoted
!     (<literal>""</>).  Reading values follows similar rules. You can
      use <literal>FORCE NOT NULL</> to prevent <literal>NULL</> input
      comparisons for specific columns.
     </para>