Re: Dreaming About Redesigning SQL

"Mike Preece" <michael_at_preece.net> wrote in message news:1b0b566c.0310300133.29098896_at_posting.google.com...
> In both scenarios one side or the
> other of the many:many relationship can be considered to be of
> "primary" importance. Do we agree on this or disagree?

I would disagree that this is always the case. (Note that having said that it isn't *always* the case is not to disagree with the idea that it is *often* the case.)

I offer the following example:

A relation expressing a graph. The nodes of the graph are cities, and the edges represent roads connecting the cities and the length of the road.

Cities:
1 San Francisco
2 Berkeley
3 San Jose

Roads:
1 2 20 miles
1 3 40 miles
2 3 35 miles

etc.

Here we have a many:many relationship, and there is only one kind of participant in the relationship. Hence, there is no way to pick one "side" as more important than the other.

Marshall Received on Fri Oct 31 2003 - 07:28:54 CET