Markus Bertheau wrote:
> is the empty array representable in PostgreSQL, and is it
> distinguishable from NULL?
Yes, and yes.
regression=# select '{}'::int[];
int4
------
{}
(1 row)
regression=# select NULL::int[];
int4
------
(1 row)
Since NULL array elements are not currently supported, attempting to
construct an array with a NULL element results in NULL, not an empty array.
Joe