Update: See this later, better explanation:
NULL
does the same thing for the overlap operator &&
as -infinity
or infinity
, respectively. I quote the manual here:
Using NULL for either bound causes the range to be unbounded on that side.
But as value, NULL
is still distinct from 'infinity'
!
SELECT tstzrange('-infinity','infinity') = tstzrange(NULL, NULL);
Returns FALSE
(not NULL
, mind you!).
More in this SQLfiddle.