Re: Review: listagg aggregate

On 1 February 2010 13:40, Pavel Stehule <pavel.stehule@gmail.com> wrote:

> 2010/2/1 Thom Brown <thombrown@gmail.com>:
> > I noticed that the regression test results don't include the following
> case:
> >
> > select string_agg(a) from (values(null),(null)) g(a);
> >
> > There is one similar where a delimiter is provided.
> >
> > Which leads me to ask for clarification, would it be safe to assume that
> > string_agg can never itself return null?
>
> if all values are null, then result is null.
>
> Pavel
>
>
>
Ah, I was looking at the expected results, and couldn't see a NULL outcome,
but then these aren't indicated in such results anyway.

Thom