Re: Determining if two subnets intersect

Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> writes:

> Florian Weimer <Florian(dot)Weimer(at)RUS(dot)Uni-Stuttgart(dot)DE> writes:
> > Is there some efficient PostgreSQL expression which is true if and
> > only if two subnets (given as values of type cidr) have non-empty
> > intersection (even if the intersection is not a CIDR network)?
>
> Maybe I'm missing something, but ISTM it's only possible for two
> CIDR subnets to overlap if one contains the other. So you could
> check with
>
> A <<= B OR B <<= A

Oh, I think you are right; I haven't paid attention. Thanks.

--
Florian Weimer Florian(dot)Weimer(at)RUS(dot)Uni-Stuttgart(dot)DE
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