Re: Query execution for intervals
From: Mikito Harakiri <mikharakiri_nospaum_at_yahoo.com>
Date: 10 Feb 2006 12:23:35 -0800
Message-ID: <1139603015.373399.124510_at_z14g2000cwz.googlegroups.com>
Date: 10 Feb 2006 12:23:35 -0800
Message-ID: <1139603015.373399.124510_at_z14g2000cwz.googlegroups.com>
x wrote:
> I would add that your interval is a set and you know the relational model
> don't like sets as attributes.
There is a certain truth in this proposition. If we consider an interval as a set of points, then the set of all intervals covering a given point (or, more generally, a set of points) is formally a relational division. Relational division is a prominent example of set join. Of course, the fact that an interval is an infinite set is very inconvenient from technical perspective. Received on Fri Feb 10 2006 - 21:23:35 CET