Re: csv format for psql

On Wed, Mar 07, 2018 at 08:04:05PM +0100, Fabien COELHO wrote:
>
> >> psql --csv -c 'TABLE foo' > foo.csv
> >>
> >>With a -c to introduce the command.
> >
> >This seems pretty specialized. If we're adding something new, how about
> >
> > psql --format=csv -o foo.csv -c 'TABLE foo'
> >
> >Or we could stick with:
> >
> > psql -P format=csv -o foo.csv -c 'TABLE foo'
>
> Currently "-P format=csv" uses the unaligned formating separators, i.e. '|'
> is used. I was suggesting that a special long option could switch several
> variables to some specific values, i.e.
>
> --csv
>
> Would be equivalent to something like:
>
> -P format=csv -P fieldsep=, -P recordsep=\n (?) -P tuples_only=on ...

We have some inconsistency here in that fewer table formats are
supported, but I think asciidoc, etc., do this correctly via
invocations like:

psql -P format=asciidoc -o foo.adoc -AtXc 'TABLE foo'

> I.e. really generate some csv from the data in just one option, not many.
>
> But this is obviously debatable.

I suspect we'll get requests for an all-JSON option, HTML tables,
etc., assuming we don't have them already.

I'm hoping we can have that all in one framework. I get that setting
each of tuples_only, fieldsep, recordsep, etc. might be a bit of a
lift for some users, but it's not clear how we'd make a sane default
that made choices among those correct for enough users.

For example, do we know that we want tuples_only behavior by default?
A lot of people's CSV tools assume a header row.

Best,
David.
--
David Fetter <david(at)fetter(dot)org> http://fetter.org/
Phone: +1 415 235 3778

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