On Mon, 2011-09-19 at 11:00 -0500, Kevin Grittner wrote:
> On a practical level, our shop is already effectively doing this.
> We have several tables where part of the primary key is "effective
> date" and there is a null capable "expiration date" -- with a NULL
> meaning that no expiration date has been set. It would be nice to
> be able to have a "generated column" function which used these two
> dates to build a range for exclusion constraints and such.
Agreed, that's a good convenience argument for accepting NULL boundaries
in the constructors.
Underneath though, we don't use NULL semantics (because they don't make
sense for ranges -- in fact, avoiding the need to constantly
special-case NULLs is one of the reasons to use range types). So, we
want to avoid confusion where possible.
Regards,Jeff Davis