Re: restore whoes

Tom Lane wrote:
> Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us> writes:
> > I was thinking of throwing a specific error when copy fails _and_ when
> > the line ends with a \r, rather than a generic COPY failure message ---
> > not sure how to do that, though.
>
> Doesn't seem practical, as the actual error may not occur till much
> later, far away from the COPY code itself.

OK, how about if we have a global char * called "extra_elog_output"
which we set before doing a /utils/adt data conversion on the last
column of the first row _if_ it ends in a carriage return. We clear it
once we successfully return. In elog.c, we print any extra string that
may be defined for extra_elog_output. I wonder if we could make use of
this other places.

Also, if we add a WITH TRIMCR option to COPY, we can suggest that in the
error message. We can add ONLYCR for Mac files ending only in \r.

>
> > I don't think I like the carriage-return -> \r solution anymore because
> > that would require people creating COPY files by hand, which I am sure
> > many do, to also escape carriage returns, which seems too MS-ish for me.
>
> We have to change *something*, Bruce, because as things stand it's
> completely ambiguous whether a \r is a legitimate data character or
> something introduced by a newline conversion. If you insist on 100%
> backwards compatibility then we'll be fighting this problem forever.
> (Or at least till Windows dies ... yeah right.)

I think we can live with it _if_ we report a proper error message and
suggest a solution. In fact, in some ways, it may be better to report
and fail rather than silently try to fix it.

> Please note also that \ r (two characters) is *already* accepted as
> meaning a carriage return. Ditto \ 0 1 5. So it's quite possible
> that applications generating COPY data may be using one of these
> representations and not be affected in the slightest.

Yes, I know, and it is obvious to COPY coders they have to escape \n
because that is their end-of-line character, but it is not obvious why
they would escape \r.

--
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