On Fri, Jan 19, 2018 at 2:07 AM, Simon Riggs <simon@2ndquadrant.com> wrote:
> err... that isn't correct. An empty range matches nothing, so can be
> ignored in joins.
>
> So probably best to explain some more, please.
The semantics of R1 @> R2 will return true if R1 is a non-NULL range
and R2 is empty.
It's set semantics, and all sets contain the empty set.
But I understand @> is an important case so I am looking into it.
Regards,
Jeff Davis