Re: revision of todo: NULL for ROW variables

On Thu, Oct 28, 2010 at 10:15 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Pavel Stehule <pavel.stehule@gmail.com> writes:
>> I am checking PLpgSQL ToDo topics, and I am not sure if this topic
>> isn't done. And if not, then I would to get some detail.
>
> I think that thread petered out because we didn't have consensus on
> what the behavior ought to be.  It goes back to whether there is
> supposed to be a difference between NULL and ROW(NULL,NULL,NULL,...)

I think somewhere along the line it was noticed that SQL says you are
supposed to treat (null, null) as null and the behavior of 'is null'
operator was changed to reflect this while other null influenced
behaviors were left intact (for example, coalesce()).

My take on this is that we are stuck with the status quo.  If a change
must be done, the 'is null' change should be reverted to un-standard
behavior.  The SQL standard position on this issue is, IMNSHO, on
mars.

merlin