Empty array IS NULL?

Hi,

is the empty array representable in PostgreSQL, and is it
distinguishable from NULL?

oocms=# SELECT ARRAY[1, 2];
array
-------
{1,2}
(1 запись)

oocms=# SELECT '{1, 2}'::INT[];
int4
-------
{1,2}
(1 запись)

oocms=# SELECT ARRAY[];
ERROR: syntax error at or near "]" at character 14
oocms=# SELECT '{}'::INT[];
int4
------
{}
(1 запись)

oocms=# SELECT ARRAY(SELECT 1 UNION SELECT 2);
?column?
----------
{1,2}
(1 запись)

oocms=# SELECT ARRAY(SELECT 1 WHERE FALSE);
?column?
----------

(1 запись)

--
Markus Bertheau <twanger(at)bluetwanger(dot)de>