"Niranjan Pandit" <niranjan81@gmail.com> writes:
> Only when the condition gets evaluated to true with at least 2 columns with
> varying values the array gets constructed, in all other cases what we get is
> a complete blank output. the label of the result is as usual as ?column? but
> there is absolutely nothing in the cell below the label.
Hmm, seems to work for me:
regression=# select array(select unique1 from tenk1 where unique2 < 2);
?column?
-------------
{8800,1891}
(1 row)
regression=# select array(select unique1 from tenk1 where unique2 < 1);
?column?
----------
{8800}
(1 row)
regression=# select array(select unique1 from tenk1 where unique2 < 0);
?column?
----------
{}
(1 row)
Pre-8.3 PG releases would return NULL instead of an empty array in the
last case, but 8,4 should not. If you're seeing differently, we'll
need a self-contained test case.
regards, tom lane