1.
Also I found next ambiguous part:
select upper_inf( '["2018-08-14","Infinity")'::daterange );
Thanks jstag from IRC for explanation that unbound and infinite are
different essence.
Thus, on the page
https://www.postgresql.org/docs/11/functions-range.html
lower_inf(anyrange) boolean is the lower bound infinite?
lower_inf('(,)'::daterange) true
upper_inf(anyrange) boolean is the upper bound infinite?
upper_inf('(,)'::daterange) true
should be spelled:
lower_inf(anyrange) boolean is the lower bound unbound?
lower_inf('(,)'::daterange) true
upper_inf(anyrange) boolean is the upper bound unbound?
upper_inf('(,)'::daterange) true
should not?
2.
I do not know, it where are any sense to distinguish:
[ 2019-01-01, infinity ) and [ 2019-01-01, )
and because:
https://www.postgresql.org/docs/11/rangetypes.html#RANGETYPES-INFINITE
This is equivalent to considering that the lower bound is “minus infinity”, or
the upper bound is “plus infinity”, respectively
and because of next statement does not work:
select '[2019-01-02,"infinity"]'::daterange @> 'infinity'::date;
if you allow I will suggest to map/convert 'infinity' value to
unbound range, for datatypes which defines 'infinity' value.
so these two become same:
[ 2019-01-01, infinity ) and [ 2019-01-01, )
It seems more consistent in compare to current behavior.
