Re: array_agg() NULL Handling

On Sep 1, 2010, at 10:12 AM, Tom Lane wrote:

> I think when that text was written, it was meant to imply "all the
> aggregates defined in SQL92".  There seems to be a lot of confusion
> in this thread about whether "standard" means "defined by SQL spec"
> or "built-in in Postgres".  Should we try to refine the wording to
> clarify that?

Yes please.

> Even more to the point, should we deliberately make this vaguer so that
> we aren't finding ourselves with obsolete text again and again?  You can
> bet that people adding new aggregates in the future aren't going to
> think to update this sentence, any more than happened with array_agg.

Perhaps “consult the docs for each aggregate to determine how it handles NULLs.”

Best,

David