"David E. Wheeler" <david@justatheory.com> writes:
> This surprised me:
> david=# select array_length('{}'::text[], 1);
> array_length
> --------------
> [null]
> I had expecte dit to retur 0. I might expect NULL for a NULL param, but not one that's defined but has no elements.
The thing is that that syntax creates an array of zero dimensions,
not one that has 1 dimension and zero elements. So "0" would be
incorrect.
Our handling of empty arrays leaves something to be desired, I agree,
but making it more consistent seems like a large task. Hacking
array_length in isolation will certainly not help.
regards, tom lane
