Re: count_nulls(VARIADIC "any")

Hi

2015-08-12 19:18 GMT+02:00 Marko Tiikkaja <marko(at)joh(dot)to>:

> Hi,
>
> I'd like to suggest $SUBJECT for inclusion in Postgres 9.6. I'm sure
> everyone would've found it useful at some point in their lives, and the
> fact that it can't be properly implemented in any language other than C I
> think speaks for the fact that we as a project should provide it.
>
> A quick and dirty proof of concept (patch attached):
>
> =# select count_nulls(null::int, null::text, 17, 'bar');
> count_nulls
> -------------
> 2
> (1 row)
>
> Its natural habitat would be CHECK constraints, e.g:
>
> CHECK (count_nulls(a,b,c) IN (0, 3))
>
> Will finish this up for the next CF, unless someone wants to tell me how
> stupid this idea is before that.
>
>
> .m
>

I am sending updated version - support num_nulls and num_notnulls

Regards

Pavel