Why is NULL = unbounded for rangetypes?

[Andreas Joseph Krogh <andreak@xxxxxxxxxxxx>]

Hi.

 

Both of these queries return TRUE because NULL means "unmounded":

select daterange('2013-07-01' :: DATE, null, '[]') && daterange('2013-07-04' :: DATE, '2013-07-30' :: DATE, '[]');
select daterange(null, '2013-08-11' :: DATE, '[]') && daterange('2013-07-04' :: DATE, '2013-07-30' :: DATE, '[]');

What is the rational behind this behavior of NULL?

 

--
Andreas Joseph Krogh <andreak@xxxxxxxxxxxx>      mob: +47 909 56 963
Senior Software Developer / CTO - OfficeNet AS - http://www.officenet.no
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