Re: Should array_length() Return NULL

On Mar 15, 2013, at 3:42 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:

>> Oh. Is there a way to declare an empty 1-dimension array?
>
> Doesn't look like it:
>
> regression=# select '[1:0]={}'::text[];
> ERROR: upper bound cannot be less than lower bound
> LINE 1: select '[1:0]={}'::text[];
> ^
>
> Possibly we should allow that, but just as with the other point, it
> would require some thought and investigation to make sure we weren't
> creating more problems than we solved.

Right, okay. I added a link to your email to https://wiki.postgresql.org/wiki/Todo#Arrays. Looks like better dealing with empty arrays was already on the list, including this gem:

http://www.postgresql.org/message-id/28026.1224611437@sss.pgh.pa.us

Thanks,

David