Re: string_agg delimiter having no effect with order by

On Wed, Aug 4, 2010 at 6:03 AM, Thom Brown <thom(at)linux(dot)com> wrote:
> Actually, this rings a bell.  I think this may have been raised
> before, something to do with the delimiter being accepted as one of
> the order by values.  If this isn't really a bug, could someone
> mention it in the docs somewhere?

Oh, yeah. I guess you need this:

select thing, string_agg(stuff, ',' order by stuff) from agg_test
group by thing;

Rather than this:

select thing, string_agg(stuff order by stuff, ',') from agg_test
group by thing;

It's all kinds of not obvious to me what the second one is supposed to
mean, but I remember this was discussed before. Perhaps we need a
<note> somewhere about multi-argument aggregates.

--
Robert Haas
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