Re: Comments on Exclusion Constraints and related datatypes

Simon Riggs <simon@2ndQuadrant.com> wrote:
> On Mon, 2010-03-22 at 10:13 -0400, Tom Lane wrote:
>> Simon Riggs <simon@2ndQuadrant.com> writes:
 
>> > * Circles, Boxes and other geometric datatypes defined
>> > "overlaps" to include touching shapes. So
>> > SELECT circle '((0,0), 1)' && circle '((2,0),1)';
>> > is true, which is fairly strange and makes those datatypes very
>> > counter intuitive. Considering they are instructional aids,
>> > this is bad.
>> 
>> You're approximately twenty years too late to propose changing
>> that, even if it were clearly a good idea which I doubt.
> 
> Possibly. We should at least document that.
 
Basically, what you feel is missing is documentation that if two
shapes share one or more points they are considered to overlap;
there is no requirement that they share an area?
 
-Kevin