Re: Why is NULL = unbounded for rangetypes?

Jeff Davis <pgsql@j-davis.com>

From: Jeff Davis <pgsql@j-davis.com>
To: Andreas Joseph Krogh <andreak@officenet.no>
Cc: pgsql-general@postgresql.org
Date: 2013-08-30T01:23:09Z
Lists: pgsql-general
On Tue, 2013-07-09 at 10:45 +0200, Andreas Joseph Krogh wrote:
> I would expect the queries above to return FALSE and have to use
> INFINITY to have them return TRUE. I don't understand what you mean by
> ranges not allowing either bound to be NULL as it seems to be the case
> (as in "it works").

Although passing NULL to the constructor works, it does *not* create a
range where one bound is NULL. It actually creates an unbounded range;
that is, a range where one bound is infinite.

NULL semantics are far too confusing to be useful with ranges. For
instance, if ranges did support NULLs; the queries you mention would
have to return NULL, not FALSE.

Regards,
	Jeff Davis