Re: [PATCH] Exorcise "zero-dimensional" arrays (Was: Re: Should array_length() Return NULL)

On Wed, Jun 12, 2013 at 1:20 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Josh Berkus <josh@agliodbs.com> writes:
>> On 06/12/2013 11:01 AM, Tom Lane wrote:
>>> I'm going to be disappointed if all we can get out of this is
>>> a cardinality() function, and nothing is done about the empty-array
>>> semantics.
>
>> Well, we can't change the zero-dim behavior without breaking backwards
>> compatibility.  And enough people piled on to say NO to that, that it
>> went by the wayside.
>
> Meh.  Robert was pretty vocal about it, but it wasn't clear to me that
> his was the majority opinion, and in any case there wasn't much
> consideration given to compromises falling somewhere between "no
> changes" and the rather drastic solution Brendan proposed.  For
> instance, it's really hard to believe that this is a good thing:
>
> regression=# select array_dims('{}'::int[]) is null;
>  ?column?
> ----------
>  t
> (1 row)
>
> Whatever you think the dimensions of that are, surely they're not
> unknown.

But, couldn't that be solved by deprecating that function and
providing a more sensible alternatively named version?

merlin